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Post Info TOPIC: What does a stock 560 SEL do in the 1/4 mile?


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What does a stock 560 SEL do in the 1/4 mile?


I am sure we can shave 5 or so seconds off our project drag Benz. I plan to be the first on video with a W126 chassis doing a wheel stand!

I think I will post cool videos of people beating the snot out of their Mercedes in this thread. Feel free to add to the list.



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LET'S GO BRANDON!

 



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I was getting about 15.1 seconds in the quarter-mile with my stock 1989 560SEC with the standard 2.47 rear end. With the 3.06 I have in there now, I don't know (yet) but I'd expect it to be in the low to mid 14-second range.



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FAR BEYOND DRIVEN

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Hello Sir,

It looks like your taking the correct path for a performance / horsepower gain..Most people so far, and they're really not informed at all, don't even know what the meaning of a horsepower even is...Believe it or not, for our considerations, it's basically a calculation derived a very long time ago, with regards to how long it takes a fit stock-horse to pull a certain weight, (33,000lbs), a known distance... So the factors up for consideration are 1-Time, 2- Weight, and 3-Distance and 4...- These 3 factors aid in determining the WORK done to achieve all this.. So, by raising the numerical value of you diff ratio, you've allowed your motor do do this work much more quickly, hence you've created more power... But possibly and likely at the cost of a lower top speed of your vehicle...
Mercedes Benz products are the end result of much careful thought, research and planning, where longevity of performance is carefully balanced with concerns to long-term durability.. What I mean to say, is that your dead stock 560 SEC is more than happy to sit on Maximum RPM, all day, everyday, travelling on one of Europes many autobahns at it's top speed (say 230-240 km/ph), this is what it's designed for period...If you want more power.. lessen the weight of your vehicle by not having a boot full of shit, and only run it with say 1/2 tank of fuel Max., to get you there and home again...Don't take passengers with you, they may weigh 100kgs+ each, and cost you your all important power.. Ultimately, what you really need to do is optimise what you already have, by taking out what you don't need... If you can carry less weight, it's free horsepower.
I personally wouldn't touch the highly refined beast you already own because the Benz Engineers know better than you or I, and any one else for that matter period !!! Have you not already considered (or tested) the fact that your car will travel, in topgear, and sit on the red-line on the tacho, all day and everyday, for the next 500,000K's or so trouble free ? I wouldn't change a thing myself, except maybe getting rid of or by-passing your catalitic-covertors, as they're nothing more than a cork in your exhaust system designed to rob your engine of much needed exhausting freedom..To overcome back-pressure in your exhaust costs you pumping losses at your piston crown, meaning less force is pushing on your crankshaft to turn your wheels more quickly, as its spent pushing waste gas out of your cylinder and into your corked exhaust...And this gets worse as RPM's increase, not to mention evaporateing any chance of natural cylinder scavenging during valve overlap etc etc...
Probably a custom set of either 4-1 or 4-2-1 (tri-Y) exhaust extactors and a free flowing exhaust system would lift your H.P. by 10 - 15% with your standard diff back in place, meaning that you get your top-speed back and get their much more quickly...Also, the most cost effective way to enhance your engines potential, is to fully balance and blueprint your motor. This is already done to a high standard at the factory, however it is a production line no less and you yourself don't have to work to a clock and could probably better the 7-gram allownce considered permissable for piston / rod assemblies etc at the factory... Also, selected and varied woodruff keys are available to optimise your camshaft timing from cylinder bank-to-bank due to the stretching overtime of your timing chain...The factory calculates an inherent 2 degrees error when new and up to 20,000 k's... How many Miles has your 560 done ??? Might be worth checking and optimising I think. I could go on and on, but I actually don't like typing !!! Good luck in your quest....

Thanks for your time,

Rastus

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FAR BEYOND DRIVEN

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Hello Sir,

It's me again, Rastus...And I also thought that you might consider this for your Drag Racing efforts....After 360 degrees of crankshaft rotation on any V-8 engine, only 4 of the 8 cylinders have provided a firing stroke... Why people who Drag Race use gear sets of say 4.11 - 1, is so that each cylinder of your V-8, has placed over 2-power-pulses to your diffs pinion gear for 1-turn of your rear wheel...This maximises the available torque output of your engine per 1- revolution of your wheel. Or rather, let me say that all 8-cylinders have fired a little more than twice per each turn of the rear wheel in top-gear, (1 :1 ratio). Calculate it out yourself.....

Cheers,

Rastus

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EASY THERE BUD................ WAY TOO TECHNICAL FOR REX TO UNDERSTAND!!!!!!!!!!!!!!!! BREAK IT DOWN FOR HIM!!!!!!


AHAHHAHAHAHAHHAHAHAHAHAHHAH!!!!!!!!!!!!!!!!!!!!!!!!!!!

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FAR BEYOND DRIVEN

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Hello Sir,

It's me again, Rastus, and I don't particularly like being told to F### Off! But I thought it best to elaborate further the considerations you may need to enhance the possibility of better results regarding your Drag Racing Quest...Talking from a "standard vehicle's" point of view, please consider these suggestions, as they're based on FACTS, and ALL ENGINEERING of any form is based primarily on KNOWN MATHEMATICAL CALCULATIONS..Engineering is all about Mathematics, like it or not.... Please take the time to think about these suggestions, as they're hard-earned and proven FACTS...

1 The Benz factory quotes 230bhp @ 4750 rpm, and 279ft/lb of torque @ 3250rpm for the 560 engine. Keep your gearshift points below say 5000rpm max (even less) as the "little window" of Max. Eng. Output is about 1500 rpm, in-between 3250rpm and 4750 rpm. Go over this upper rpm threshold, and your moving forward more slowly than you would be by selecting the next gear and revisiting this window of Max Torque and BHP.

2 Use the best (highest octane number) fuel you can find and also the freshest.(Aviation fuel for Light aircraft is the best, but highly illegal to use and probably hard to get, and also quite expensive...). Each drop of fuel (or gram rather) has the potential to release approx. 142,000 + kj of energy...This equates to about "140Bar +" peak pressure inside each of your 8-cylinders. The efficiency in which your engine converts this potential energy is what you need to harness...The CISE fuel distributor on your 560 engine is tuned to meet strict Californian emission levels, not the optimum "Stoichiometric"air / fuel ratio of 14.75 : 1. You can adjust this by removing the little yellow plastic cap on your fuel distributor, and by then using a 3mm allen key to richen the fuel mxture. Turn clock-wise, very slowly and in very small increments until the engine begins to "run rough", then back it off, and do it again until you find that nice sweet spot..."If you want more horses, you've got to feed them..."Very important to re-fit a new yellow plug as this maintains a steady fuel mixture, eg, no air-leaks.

3 Use say Shell full synthetic Engine oil, as its lighter weight/viscosity reduces puming losses at your oil pump ( more power as there's less oil drag every-where and better protection ).

4 Consider the same Synthetic Oil option for your Transmission and Diff for the same reasons. (Slick-50 is also a proven trade secret that really works).

5 A wheel alignment is crucial, as if the wheels aren't pointing where they should, they're scrubbing out costing you Horse-power to keep the car in a straight line. Don't underestimate this, as the scrubbing gets worse as you go faster, costing you more power. Try picturing 2 wheels, one pointing straight ahead, the other pointing say 2 degrees to the left. After say 1km, how far has the offset wheel moved away from the other going straight ahead ? This distance is what your engine has to make up in terms of power from scrubbing, to keep your car going straight ahead. Use correct tyre pressures also...

6 Remove your accessory drive belts before you drag, that drive your A/C & Power Steering. Both these items might give you an extra 5-10 bhp to drive your car further forward faster once removed...

7 If your doing burn-outs off the line, your'e not moving forward as fast as you can to the finish-line, so regulate your throttle movement off-the-line to avoid a burn-out.

8 Possibly the best(?) alternative that's not a stock item to your car, would be to fit a " Hi-Stall Torque Convertor " to your Transmission with it's requisit Oil Cooler. If you can find or have one of these babies made to suit your needs ((3,250 rpm is where peak torque occurs so aim for this figure(stall speed)) You will be able to access this "sweet spot" of your engines Toque at any time, any gear, any where....You need pure Torque in ubundance to "pull you off the line" with a car that possibly weighs in at close to 2000kg.

I do hope you consider these suggestions, as they WILL HELP, and I'm NOT a smart-ass, as I like a good performing vehicle as much as anyone. I've maybe delved a little deeper as to what needs to be done to achieve these things. I would advise you to not use the internet as your only source of information, but to buy and read a number of different performace type books, and then cross-reference all the common revelations, as these are the general facts that each different author (and now yourself) would have determined individually, as to what really makes things go faster. Every car/ engine and combination(s) is different to the next, and what works for one won't necessarily work for the other. Just look for the simple things first, and remember that your Engine can be thought of very loosely as an air-pump, so the bigger the pump(motor) to start with, and the more air that you can let into it, and escape from it, the more potential for power output can be harnessed...Enough said. I hope I've explained things in a more digestable manner (as suggested by another sight user) and hope you have fun working thing out...

Happy motoring,

Rastus

P.S. What car do I drve you may ask ? I'll keep it my secret, but I do now finally own a Benz, and it happens to have a nice 8-cylinder orchestra that performs beautiful music !














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Rastus wrote:

It's me again, Rastus, and I don't particularly like being told to F### Off! 


 Don't pay any attention to Ronnie Stoma Jr. His brain is the size of a pea, and you can see from his posts here that your average Japanese car's horsepower rating is several multiples of this individual's IQ.

He has no known mechanical ability, and has never posted anything of substance about working on cars.  So it's best to ignore everything he posts and just deal with the folks here who actually work on their cars, race them at the drag strip, and so forth.

Here is a post of me, taken some years ago now, racing my 1994 E500:

 



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BUUUUUUUUUUUAHAAHHAHAHAHAHAHAHAHHAHAHAHAHAHA!!!!!!!!!!!!!!!!!!!!!!!! HEY GAYRRY........ HE'S TALKIN ABOUT A 560 AND NOT A 500E!!!!!!!!!!!!! LOOK AT YOU WITH YOUR CASCADE MOMENT..................... WAITING FOR THE OPPORTUNITY TO POST A VID OR PIC OF THE 500E WHEN NO ONE HERE ASKED FOR!!!!!!!!!!!!!!!!!!!! AHAHHAHAHAHAHAHAHAHAHHAHAHA!!!!!!!!!!!!!!!!!!

THOSE VIDEOS SHOW JACK SHIT.................... CAN'T SEE TIMES AND EVEN BETTER................ CAN'T TELL WHO WON!!!!!!!!!!!!!!!! WHAT A FUCKIN LOSER!!!!!!!!!!!!!! AHHAHAHAHAHHHAHAHAHAHA!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! NICE TRY FAGGOT!!!!!!!!!!!!!!!!!!

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FAR BEYOND DRIVEN

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Hey man,

It's Rastus here, and I checked out the vids you posted above, and yeah, the 500E Rocks ! I know that nerves, adrenalin, and a strong desire to blow the other guy away ( and a whole lot of other stuff) are running through your mind at the start line, but you must remember to change gears well before the Red Line to keep you moving forward faster. Every engine when you reach it's high revs, wants to "hang-there" and keep hanging,- this is no good because that's your motor saying "I've got no more to give, please change gears, but I'm happy to stay hear if you like". I noted that (possibly it was your Benz) the Rev limiter was cutting you out at least twice through the run. Even though you smoked the guy, you would still have been better off to change gears much earlier and left him further behind, and improved your times. That being said, well done, and the more you do it , the better you learn what your car can / can't do and when, plus you'll learn to relax a lot more, and that's when things will start moving more quickly for you, just relax...
Also, I've made an error in my last post when I advised you to remove your power steering belts, do this only if you can find a smaller pair of belts ( at some tension) to still drive your water pump, - whoops, my mistake...Also, I do Know that the very early 3.5 ltr Benz V-8 came out standard with a 2,350rpm stall convertor as standard fitment from the factory. Should this thing fit to your 560's transmission,( it's quite possible and likely but I don't know, but it does have a 310mm diameter which is the same as the 6.9...), with the extra output (torque) available from your motor, this "stall-speed" will more than likely increase a little more again, bringing you closer to your Torque/Power window. Check it out, because you could probably buy a whole car in good condition for not too much money, and find lots of other goodies that may possibly be used in your 560. Eg. Cylinder heads to up compression ratio, the 3-speed trans is possibly a better choise for drag-racing as the gear ratios are " shorter " and less gear changes required (this costs you time), and you never know, even the camshafts maybe a direct swap-over to you engine. The 4.5ltr engine only came into existance because "emmision laws" robbed the smaller 3.5ltrs engine of it's power and torque, which means that the 3.5ltr is actually in the "highest state of tune" as designed from the factory... The 4.5ltr (as nice as it is) is nothing but the same motor only stroked by around 20mm... Your 560 is nothing more than an attempt by the factory to restore the power being robbed from the 5.0ltr at the time by emmission laws. At the end of the day, all this Engine Family is essentially derived from the original 3.5ltr design, no shit, and it's output ( according to SAE standards ) was 230bhp @ 5800rpm, and 286 Nm @ 4000 rpm. Your 560 makes 237bhp @ 4750...All engines manufactured during this engine-families life cycle are nothing but modifications in capacity to supplement the power losses incurred by toughening emmission laws, that robbed the original 3.5ltr engine of it's full potential....However, Cubes is Cubes, and the more the merrier..
Have fun, and I'm sure that there's some-one out -there that's been there and done it, with a little bit of luck, you might meet or speak to him/her. I'm also in NO WAY SAYING DO THIS OR DO THAT, but just trying to expand you knowledge of what's out there, why things happened in the past, and what you might be able to do or find out with a little bit of investigation.

Rastus

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FAR BEYOND DRIVEN

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Hey man,

In case you're wondering what these emmission constraints were all about, they were essentially a government dictatum requiring all manufacturers to lower the exhaust emmissions from their new vehicles by a certain percentage, and to follow more revisions year after year....Starting more or less from the late 1960's, and still on-going to this day. Most manufacturers will spend years (up to 5+ years for Benzes ) in the design, R&D, prototype testing and developement of their products / engines, with the intention of 5+ years of production relatively unchanged, or with minor enhancements. This caught a lot of makers by surprise,as they all want a slice of the"American Pie"market place, as your the largest consumers of this market type world-wide. So these manufacturers, world-wide, had already spent millions of dollars in developement of their products, and were now forced to add "bolt-on" emmission reducing items such as air-pumps (these blow fresh air directly into the exhaust manifolds to burn away unburned fuel), EGR Vaves ( these recirculate exhaust waste gasses back into your intake tract to be re-burned, and lower peak combustion temperatures), Electrically Controlled Vacuum Advance to your Distributor in top-gear only (via a switch located on your transmission) etc. etc. All these things added up to Much Higher fuel consumtion, loss of power, but apparently lower emmisions.
One of the main tests for emmission out-puts, was to determine exhaust emmisions at speed, during highway use, over a certain distance...( I think it was a mile in length, at 50 mph, and measuerd in parts-per- million, then calculated as a percentage). The quickest and easiest way for manufacturers to overcome this particular hurdle (and a lot did so ), was to fit a numerically lower diff-ratio, thus lowering emmission output due to much-lower engine rpm, over the required distance...This cost the consumer in performance output..So what you were left with was cars that drank more fuel, performed terrible when compared to the same spec. vehicle made a few years earlier, but met the required emmision out-puts. So the next trend for manufacturers in restoring performance to their vehicles, was to increase engine capacity, and of course this leads once again to higher fuel consumption and cost to the consumer, but provides the legal requirements of the governing bodies.. Then of course Un-leaded Fuel and Catalitic convertors become legal requirements in 1976(?), and the same cycle happens again, - eg. engines grow larger to try and maintain performance, whilst emission levels are "apparently" reducing, whilst our fuel bill is growing quite considerably for the same(?) performance.. Kind of sounds like a scam doesn't it ?
Your going to have to work out some numbers for your drag racing quest man. Ask youself these things...
1 What is my terminal speed over the finish line ?
2 What gear am I in ?
3 What RPM am I doing over the line ?
4 Can I take off in 2nd, to reduce the number of gearshifts through the race ( each gearshift possibly costs you 0.2 sec.s) ?
5 What diff ratio will give me Max. rpm over the line, at best speed, within the little window of Max. Torque & Power out-put ?
6 Can this be done or am I better of racing over the line in 2nd or 3rd gear ? (a standard 560 will change from 2nd to 3rd @ around 160 km/ph, and 3rd to top @ around 220 k's, so I figure your probably in 3rd gear for memory)
7 Do I need to extend my gearshift points with a lower diff ratio to minimise gearshift changes, or to I need to go the other way ?

Have fun man,and I hope your times get better !!!

Cheers,

Rastus

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FAR BEYOND DRIVEN

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Hey guys,

I haven't seen anything posted here for a few days, so I figured you might have gone racing over the week-end, so how did you go ? I thought I might take another opportunity to perhaps clarify the camshaft phasing of this engine family (M116's & M117's), and how you might like to "enhance'' this somewhat...

1) When these engines are new, there's an approximate 2-degree error in the phasing of the camshafts, from cylinder bank to cylinder bank, that by 20,000k's, after timing chain stretching and settling, brings the 2- camshafts back into phase. Should this not occure, woodruff keys of nominal sizes are available to bring the out-of phase shaft(s) to the correct specification.

2) I will not explain step-by-step how to do this except to say that you must keep tension on the timing chain by having rotated the crankshaft in the correct direction of rotation ( clock-wise when looking from the front of the vehicle. (99% of all engines in cars spin in this direction, though there are exceptions, eg, some early Honda Preludes etc etc)), and by taking a measurement of the valve lift happening on say cyl. No.1, at some amount of degrees After TDC. Your figure is determined by crankshaft degrees after your valve has opened 2mm...

3) Once you have gone to the trouble of bringing the camshafts into their correct phasing, you will notice a substatial improvement in the way your motor performs, particularly with throttle responce, and overall output / power delivery etc etc. You will also be starting to exceed the factory quoted HP figures, as they're always conservative..

4) Anumber of manufacturers like to be able to make say 2- engines ( or more ), of 2-differing sizes ( or more), from the one basic design, as this reduces their development costs, by "killing 2 birds with the one stone" etc etc. This also allows a number of parts inherent with the design to be "shared" from one engine to the other, eg, oil pumps, Valves and Valve-springs, #Camshafts#, and lots of other bits and pieces.( Did you know that the Benz 350, 450, 380 & 420 all have 92mm pistons installed ? They may vary in design, but they're all 92mm).

5) With regards to the use of the same camshafts accross the range of differing engines, manufacturers "discovered" that by RETARDING the camshaft timing on the larger engines, top end power out-put increased without the loss of low-end torque. A typical figure of redardation is 4-5 degrees, but this may not be the figure that's optimum for your 560, you'll need to play around, and I would advise you NOT to go beyond this figure due to poss mechanical damage occuring-eg valves hitting pistons etc. This revelation is common to all engines that use camshafts with intake and exhaust lobes common to the same shaft. The later opening of the intake valve actually provides a stronger negative pressure (signal) in the cylinder that enhances top end power out put by having better cylinder filling potential as the piston has moved down the cylinder further before valve motion has began. It also allows for an earlier opening exhaust valve to aid in cylinder emptying...Remember that with Benzes, the 450 becamme the 500, the 500 became the 560...

6) Regarding your exhaust system, ALWAYS USE A TWIN EXHAUST WITH A V-8 ENGINE !!! Regardless of what the "experts" tell you. When people tell you that you need "some back-pressure", they're talking shit and know Zero about prformance enhancing engines. The more back-pressure you have, the less horse-power your making. Don't under any circumstances be talked into a "Big- Bore Single System". always with V-8 you need a Big-Bore TWIN-SYSTEM.

I hope all this makes sence to you, I've tried my best to keep all this in plain English so to speak, and everything I've mentioned here I can back-up mathematically, as numbers don't lie -(though they sometimes don't add up !) Have fun and speak soon !!!



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YOU CAME TO DA WRONG FORUM MY FRIEND.................... YOU ARE IN A WORLD OF SHIT NOW!!!!!!!!!!!!!!



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FAR BEYOND DRIVEN

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Hey guys,

I don't suppose you could send this guy (above) around to pay a visit to Ronnie Stoma jr. ?

I realise that you folks are serious about your racing, and you "Put Your Money Where Your Mouth Is" so to speak, as having now had a look around the forum proper, the only reason why I post the "blurb" that I have so far, is not to advise "you folks" about what to do, (because your already doing it) but for other folks out there who visit this site, and post nothing because they've maybe gotten nothing out of it except maybe a laugh !

Fair enough !

I just figured that some people might also like to learn about some possibilities about what they might want to try out on their own, and maybe come knocking on your door to "drum up some business", and get further advice/guidence as to what they might be able to do to get their own 560 cracking the low 14's or better..

There is a lot of laughs, and a lot of problem solving to some degree goin' on here, but probably not a lot of "content" to keep your mind ticking over about things when you log off, - which is all I was trying to do !

So in finishing, I just wanna say that Ronnie Stoma jr, you suck !!!

Cheers,

Rastus


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Dude,

I appreciate your posts. They are thought provoking and informative, and that's what counts.

You are right on with your assessment of RSJ. He is best worth ignoring and only referencing indirectly, not in a direct way. RSJ is not worthy of direct conversation from anyone on this board, with the possible exception of his pal PowerStroker.

Cheers man !

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Thanks gerryvz,

I figure you guys have enough to deal with, let alone the likes of RSJ....

I'll post this next submission with the intent of at least trying to provide an overall assesment of what one might well get out of "trying" some of the suggestions that I've posted so far, as who knows, some of you out there might well be busy with your head-under the bonnet looking for some results...(I hope so at least !)

Please consider these methods as mentioned, and place them into some practical perspective (or outlook rather) please...

Let's say that some of you have tried to go about improving your vehicle with some of my 'blurb" mentioned so far...

Let us also say that you've tried-out 10 items as mentioned above... But have only found at best a 1% improvement per item that you've worked on or modified...

This 1% improvement per item equates to a grand total of 10%...

10% of a 15.1 second 1/4 mile result is equal to 1.51 seconds...

1.51 seconds taken off the 15.1 seconds recorded officially so far, is equal to 13.59 seconds...

Kinda makes you wanna get under the bonnet and start doing things doesn't it ?

A result like this is all that I was hoping to help others achieve, and to at least get out there, do some work, have some fun, and see what happens...That's what it's all about isn't it, - having some fun ???

Also, if your like me, and don't have access to a dyno to fine tune your beasts in a near "real world fashion" before you get to the drag strip, you could try this formula to calculate your Horse-power...It's reasonably accurate ( a fair approximation only !!!), as it incorporates the basic overall factors involved with your car and its times, so try this, and I'll use the 560 results as posted above as a guide, and go through it step by step....

1) We have to convert our known figures into "base" units, so that they calculate out as best as possible. Our formula will involve 1- Vehichle weight in Kg's. 2- The force of Gravity in Kn's ( This is kilo- Newtons). 3- Friction Force ( This is a nominal value of 0.4 used world wide by engineers for calculations and has NO UNITS, it's a "co-efficient"...). 4- Distance in Kilometers. 5- Time in seconds...These figures when calculated will give us a result in KiloWatts...We then multiply the result by 1.34 to get Horse Power.

1 Vehicle weight we will call 1800 kgs (for purpose of example only, as I don't know what "your" 560 actually weighed in at on the day)

2 The force of Gravity is 9.81 Kn

3 Friction Force is a nominal value of 0.4

4 Distance in Kilometers is 0.4 km

5 The resultant time is 15.1 seconds

The formula reads like this Kg x Kn x ff x Km / Time..... So lets put the numbers in and calculate.....

1800 x 9.81 x 0.4 x 0.4 / 15.1 = 187.104 Kw Multiply this by 1.34 to get Horse power.... 187.104 x 1.34 = 250.72 Hp

So, you could quite happily quote to your friends, that on this day, at this time, my motor and running gear combined, managed to make this much Horse-power, to pull me over the line with this time... I reckon this figure is probably a reasonable approximation, and it at least gives you something to work with and talk about !! Have fun !!!

Cheers,

Rastus







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Hello Guys,

It looks like whatever you've done or said to RJS has worked !- ( For the short-term anyway !).

I was thinking that perhaps as a rough guide, that if you weren't too sure about what Horse-power numbers are considered "safe" for your engines, that won't affect long term durability, there's an old "rule of thumb " that still holds up well today, as it did yesterday....

Generally speaking......The best figure to aim for is 0.8 - 1.0 Horsepower, for every Cubic Inch of engine displacement......So how do you get this figure when your engine capacity is in Litres ? All you have to do, is multiply your known capacity ( in litres ) by 61. Approximately 61 cubic inches is equal to 1 litre.. This means that your 5.6 litre Merc engine displaces about 342 Cubic inches...Should we then multiply this by a conservative 0.9, we arrive at the figure of about 308 Horse power...You can of course go straight to the 342 figure, (when multiplied by 1.0 ), but this would possibly be the upper limit of maintaining your reliability. - (this may seem like a small figure, but it is 100hp over a standard engine, and look how well it goes...). You may also find that the fuel injection system could be reaching it's Maximum delivery capacity beyond this thresh-hold...This is when things will start getting expensive, as you now have to buy aftermarket products, that will throw an in-balance into the overall design and operational characteristics of your motor, not to mention a depleteing bank balance.

Should you decide to want to go further, (with regards to a carburetion aspect), the " general" rule of thumb has always been to aim for a carburetor (cfm) of about 2.0 - 2.3 times the size of the engines cubic capacity...eg, 342 x 2.3 = 780, this would mean that a single 780 cfm ( Cubic Feet per- Minute ) Carburetor could be used...(You should be asking yourself now what's the diameter of my Bosch CISE throttle valve, and how does it compare to the added total of the 780 cfm carbs 4-throttle vaves in size ? If it's large enough or larger, how do I get more fuel delivery through the injectors ? What is my current fuel pressure at the distributor, and how much can I increase this pressure ? Do I need a higher pressure fuel pump / Can I get one ?)...Am I getting full throttle ?

Possibly the best Carburetor to consider for your type of application, would be to source one called a "Predator."...This is basically a self calibrating fuel metering device that's been shoeboxed into the Carburetor catagory....By all means they work very well, but you'll drink more fuel... Always remember that if you want more horses, you've got to feed them...

The possibility of a tunnel-ram and multiple carbs exists, however drivability will suffer dramatically, you'll be forever tuning the bastards, as they always go out of synchronization ( you'll have two carbs working at once remember, so this means two throttle vaves (at least) that have to open and operate at exactly the same time and range..) and you'll consume fuel like you wouldn't believe...Not to mention a very large hole in the bonnet to fit it all...

Tunnel ram set ups are hard core, and specifically tuned for an operating RPM range that's usually quite narrow, maybe a peak power range spanning all of 1,000 rpm that you then have to determine with camshaft selection, diff ratio, and a finely tuned twin-system exhaust...All working together harmoniousely...Very expensive stufff, but it can be done...

All of this is playing around really, and probably doesn't belong in the realm of a Mercedes Benz motor vehicle, however, at a certain predetermined point inherant within an engines design, if you want more power, and can't increase the engines displacement (capacity), you have no choice but to find more RPM. This means camshafts, induction system mods, and exhaust-system improvements, you cannot avoid this...

Wow, where did all of this come from ? I hope I didn't put you to sleep, or wander too far left of centre...Just trying to give you guys more food for thought and things to think about, as sometimes seeing things from say a carburetors point of view can help you understand what you aready have under you bonnet...or what you might need to do to get things going along a little better. I do hope to hear or see something written soon, even a question or two to get me thinking proper again. Have fun !

Cheers,

Rastus


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I guess someone forgot to tell Bugatti about this little "Rule of thumb".

What with it's W16 quad turbo engine pumping out 1000+Hp maybe they are on to something?

The formula for HP has always been the same,

$ = HP

LOL



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gerryvz wrote:

Yes, I find around 10 1/4-mile runs with my 10-pound bottle is about all I get. I remember how everyone under the sun was insisting I was going to blow up my motor, die in a ball of flame, rot in hell, etc. if I installed the nitrous kit (which is a modified 5-liter NOS brand Mustang box kit), 100-shot. Well, 9 years later my engine is still kicking.... and I'm still around to give RSJ, PowerStroker and ManBoobs McClare plenty of shit.

Well Gerry, the 5.0 Mustang Dry kit is a very good kit and it fits way more cars than just the Mustang, Mercedes and Camaros. It just got a great reputation with the 1988-1992 Mustangs because them models come from the factory with forged pistons and people REALLY abused them without any damage.

Truth be told I usually had my bottles overfilled by 1-2 lbs and used a mini-propane torch to heat them up till they just started to reach the pressure where the blowoff valve would start purging the nitrous. People thought I was crazy, but there really is no feeling like that first race with a hot overfilled bottle. I would literally spin a set of 10.5 inch wrinkle wall slicks @10.5 psi pressure properly heated (burn-out) with VHT compound. Thats no small feat, in fact I have torn out numerous torque boxes, literally ripped them from the frame. Torque boxes are the steel cages that hold the lower control arms that hold the rear axle (on a Mustang). I have not been brave enough to try this on a Mercedes yet, but I imagine the flex discs only survive on many of these V12 modified SEC coupes *cough* Satish *cough* because the tires break loose.

I should add the guys filling my bottles always looked at me funny when I would bring in soot covered bottles with the blue paint burnt off. LOL Sometimes I would really have to lean on them to overfill them, but back then Hamilton would always sway them to my way of thinking.


You are right that I have a conservative install. I could jet it upward (I tested the fuel system...remember my nitrous kit is a dry, not wet kit) to 125 HP, but I'd feel uncomfortable going beyond that. M119s are considerably more expensive used than M117s too. I'd love to install a NOS system on my SEC, that would be a nice complement to the 3.07 rear end that I installed about 8 years ago....

I use to think 125HP was a lot of Nitrous! LOL, and I use to think the small 5/16 supply line was big too! LOL That was until I started messing with Big Shot kits in the 300-400 HP range that came with garden hose sized supply lines. LOL.

M117's are pretty expensive too and in my opinion they are more of a pain in the ass to work on than the later M119's because a lot of things changed with regards to the way the camshafts were mounted to the heads. But I do agree the M119 has more valves, springs, keepers and such so naturally there is more money there should it blow up. Not to mention M119 parts are generally a bit more expensive too.

I can see why you worry, and I tip my hat to you for having the balls to use even a dry kit. Most are just too much of a pussy.

Now, I've got to head out to the garage to "de-ASR" my car.... ;)

LOL! What an accomplishment that would be! LOL!




-- Edited by SELLC on Friday 1st of June 2012 12:16:51 AM

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Hello guys,

Yeah, a very nice "bit of kit" to say the least ! I don't suppose you could tell me it's capacity, (maybe I should just look it up...) ? It's pretty much the "state of the art" with 16 cylinders and 4 (!!!???) turbo chargers ...Whoah !!! I sure wouldn't want to be the transmission or diff !!! Has any body got any times of the beast down a 1/4 mile, as it would be interesting to punch the time and weights into that formula posted up above, just to see how many Hp make it to the ground over said distance ? Very nice post, thanks SELLC !

I know turbo charger development improves in leaps and bounds year after year, but I tell you what, it's virtually impossible to ever "perfect" a turbo chargers performance, simply because of the nature of an engine going through the motion of changing gears. To elaborate a little, when you've just reached peak revs and changed gears,(say 2nd -3rd) your turbo would be "over-spinning" for the now lower requirements of the motor, so it's kind of always "cycling" between delivering too much, or too little, especially in the lower gears, hence the term "turbo - lag". Even if you can regulate the waste-gate movement with your gear-ratios etc. you'll always be chacing your tail and it will never be "perfect", though no doubt development gets closer and closer every year. I say let em go for it !

Very nice indeed, and you guys are obviously working on the right stuff !

Cheers,

Rastus

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Hey guys,

I just did a little searching on the net, and though a little hard to find, some specs. were available, and I thought just for a point of comparison with regards from 1/4 mile "only" perspective, the result I've calculated you may find interesting....Remember this is from a 1/4 mile perspective only....

The weight of the car is actually quite high ( I thought ) at 1,888 Kg's. Must be for high speed stability at 400+ km/ph.

The displacement of the W16 engine is 7,993cc's or if you rather, say about 488 Cubic inches, ( Yes, this over double the '"old rule of thumb" figure generalized earlier, but remember it's been designed from scratch to do this, so realistically the rule doesn't apply as we've already exceeded it's perspective yes ?).

However, the given 1/4 mile time for this Bugatti is surprisingly in at 10.2 seconds...

So using the formula as posted earlier, the amount of Hp delivered from the car over the 1/4 mile is not as large as you may think....

We have 1888kg x 9.81N x 0.4ff x 0.4Km / 10.2sec's = 290.53 Kw. This multiplied by 1.34 is equal to 389.31 Hp..

So it looks like the designers have limited engine out-put in the interests of safety and traction, to provide the Max output at the high speeds the cars capable of.

I hope I'm not wasting your time or anything, ( or making out to be a smart ass or anything like that ), I just wanted to put things into a "clearer" perspective from the 1/4 mile point of view. Have fun !

Cheers,

Rastus

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It is true that the Bugatti only needs a little over 400 HP to make near 9 second quarter mile times, however the other 600+ HP is needed to get it up to the 220+ MPH.

You see the game changes when you start getting over 140 MPH due to the forces of wind drag.

All told 10.2 seconds in the 1/4 mile is SUPER fast for a vehicle that can also do 220+ MPH. Most cars that can muster up even 11 second 1/4 mile times are all gear and could never bust 160 MPH on the top end let alone crest the 200 MPH mark.

The thing here with the Bugatti's 4 turbos is that many of the issues you mention in your post are not so much of a problem, as they work together to overcome these problems. One must not forget the Bugatti's $1,000,000.00 + Price tag either.

However Fords EcoBoost engines utilize a twin turbo setup that also works to overcome the issues of single turbo's of yesterday. The EcoBoost also utilizes a very high pressure fuel system for state of the art atomization of said fuel.

I myself am not a big fan of Turbo Chargers, Superchargers or Blowers. I am more of a Nitrous guy, but thats just because I grew up using the stuff.

I welcome anyone's thoughts and formulas when it comes to performance, so don't ever feel like you're being a smart ass by driving home valid points or new ideas. These things are always welcome here! 



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The best I've been able to do with my E500 with nitrous is a 12.89 second quarter mile, at a little over 108 MPH. The stock time for said car, normally aspirated, is 14.1 at a high-99 MPH speed.

Nitrous is the shizzle, but it's only usable for short acceleration runs. It would be nice to have all that additional power on tap all of the time, say with a supercharger. A local shop owner here in Houston with a 1993 500E installed an Albrex supercharger. I took a lot of photos of that car. Unfortunately the photos caused quite a few of my board members to get woodies.

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I disagree Gerry... I find that Nitrous, when used properly is able to be used when needed to achieve victory in almost any situation.

There are things such as large bottles, bottle warmers, and remote bottle openers that allow you to pretty much have nitrous on tap whenever its needed.

I understand that you have used small nitrous kits Gerry, and they are pretty safe. Hell I used to run back to back 1/4 mile passes all night long with my Mustangs back in the 90's. These small kits use relatively small amounts of nitrous and you can get about 12-16 1/4 mile passes out of your standard bottle. That's a lot of wins considering no one races for free, so your first win pays for the other 15 passes.

What I found with the small nitrous kits is that it becomes not enough after awhile, so I made a dual stage kit. The first kit was my reliable dry kit with 5/16 or so hose. The next kit was a BIG SHOT kit with a 5/8 hose. The big shot kit was wired thru all the safeties of my dry kit so it would shut down in the event anything went wrong. What I can tell you is this... With 400 HP worth of nitrous it's like NOTHING you ever felt. The speed in which the RPMs climb is almost mind blowing. There is NOTHING like it and I have driven vehicles with Dual Turbos, SuperChargers and Blowers.

Hands down nitrous oxide is the best bang for the buck in terms of competive racing on the street or drag strip. It is introduced to the engine at below freezing tempratures making for a dense air charge, and it does not take away any power from the engine to opperate, either in drag or restriction.

Nitrous is good stuff.



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Thanks SELLC,

You're very much "up-to -date " and I have to agree with you about not being a fan of turbos or blowers. And thanks for bringing me up-to-date with who-what-&-whens of what's getting certain times down the 1/4 with the trade-off of top end speed. It does put a vehicles "over-all" abilities into perspective. Wind resistance is something that's always underestimated, and often something you can't do a lot about as your basically "stuck with what you've got " !

Mecedes Benz engines are very well made and designed as you already know. And in case you didn't know, all their crankshafts are made from steel and one forging, and are stress-relieved via the use of the freezing process (I think) called nitriding...All the con-rods are steel forgings also...Very nice... Combined with the 4-bolt Main Bearing fastners, there's a very strong and reliable Bottom-end assembly living there, which is the main reason why they have sustained high rpm reliablity, day after day, year after year...The reason why I'm pointing this out to you, is that I believe you could easily get 400 + Hp out of your 560, and have reliability, but I think that maybe the fuel injection system may end up being your limiting factor, and I would probably ask you to consider a move back to the older Bosh D-Jetronic fuel injection system... Don't laugh !

Why you may ask ? I would put it to you that the main advantages you would gain come from the fact that you could have your own throttle plate maufactured to your own desired size, to handle the more air-flow required of a higher peak power output at higher RPM, and the fact that you could choose your own capacity fuel injectors to meet these demands, as they're all linked to a common fuel rail loop, and timed to open at varying time intervals, depending throttle position, rpm, air -temp etc etc. via the ECU, which I dare say could be easily(?) modified or mapped rather to suit.

Another alternative is the "Ma Gee "(?) EFI set up that actually lets you set up your air fuel ratio in real-time as your driving along, with LED display that lets you know in "real-time" what's going on mixture wise at any rpm, load, and throttle position etc. Perhaps a "hybrid" combination of the two is the go ?

At the end of the day, this type of injection system will let you determine your own volumetric efficieny (cylinder filling potential), at any rpm, as compared to the CISE system that limits this by having an Air sensor flap (restrictor!) connected to the plunger in your fuel distributer, that lives above your throttle plate.( This system by design gives a progressive cylinder filling ability) This limits the amount of air available to your cylinders, particularly at lower rpms, as you have a "see-saw" effect occuring between the flap and plunger, regardless of throttle position as it's the engines increased negative pressure (within each cylinder that grows with increased rpm ) that pulls this "air flap" down further, allows more air in, and also moves the plunger in the fuel distributor to deliver more fuel through the never closing injectors. It's a great system, but limited, especially for outright performance increases.

Also, with regards to balancing your piston/rod assemblies, it's actually easily done with the use of electronic scales that are suitably calibrated,-( or any type of "scales" as long as they're accurate and can sustain the components weight ). All you need to do (after numbering each assy.) is to weigh each piston / rod assy, note the reading of the lightest one, and then bring the weights down of the others by carefully grinding away excess metal from the lower "pad" provide on the bearing cap. When the weights are all equal, the assembly is optimised by being lighter overall, equalized, and you've removed an enormous amount of bearing load (in Nm) that increases linearly as the rpms go up. Your engine will have even more improved reliability.

Cheers,

Rastus


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Agree that nitrous is good stuff. Yes, I find around 10 1/4-mile runs with my 10-pound bottle is about all I get. I remember how everyone under the sun was insisting I was going to blow up my motor, die in a ball of flame, rot in hell, etc. if I installed the nitrous kit (which is a modified 5-liter NOS brand Mustang box kit), 100-shot. Well, 9 years later my engine is still kicking.... and I'm still around to give RSJ, PowerStroker and ManBoobs McClare plenty of shit.

I do have a bottle heater and remove valve installed on my system, and the bottle is mounted at the correct angle on a custom-fabbed bracket that sits down in the driver's side trunk side well (like a 126 sedan has).

You are right that I have a conservative install. I could jet it upward (I tested the fuel system...remember my nitrous kit is a dry, not wet kit) to 125 HP, but I'd feel uncomfortable going beyond that. M119s are considerably more expensive used than M117s too. I'd love to install a NOS system on my SEC, that would be a nice complement to the 3.07 rear end that I installed about 8 years ago....

But hey, I'm the first to admit I'm an amateur at this stuff, so by no means am I bragging or trying to be something I'm not.

Now, I've got to head out to the garage to "de-ASR" my car.... ;)

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Rastus wrote:



Mecedes Benz engines are very well made and designed as you already know. And in case you didn't know, all their crankshafts are made from steel and one forging, and are stress-relieved via the use of the freezing process (I think) called nitriding...All the con-rods are steel forgings also...Very nice...

I agree.. Mercedes Crankshafts are some of the nicest I have ever had the pleasure of holding in my hands. Unlike many others they are always flawless in terms of machieen work. The journals and counter weights are always flawless, never any dimples or craters. Hell they are even more flawless than $2000 4340 performance cranks you see for sale by aftermarket companies. They really are a work of art!

 Combined with the 4-bolt Main Bearing fastners, there's a very strong and reliable Bottom-end assembly living there, which is the main reason why they have sustained high rpm reliablity, day after day, year after year...

Actually Rastus, the M116 and M117 engines have a SIX bolt main. 4 on the top of the main and two on the sides that go thru the sides of the block (with the exception of the #1 main cap). ;) Not only that, four of them six are main "STUDS" which are much stronger than a "bolt".

The reason why I'm pointing this out to you, is that I believe you could easily get 400 + Hp out of your 560, and have reliability,

I think people fail to realize that a factory 560 engine is closer to 260 HP with emissions removed. So the magic 400 number was just a small dry nitrous kit away for me. I have had success with a small kit on my 560 back in the early 2000's but after I ripped out a set of engine mounts doing a burn out I decided to leave stuff to a "Race Only" Benz and keep my daily driver as-is. In making that choice I am still driving that car today, EVERY single day without issues or problems as reliable as can be.

but I think that maybe the fuel injection system may end up being your limiting factor, and I would probably ask you to consider a move back to the older Bosh D-Jetronic fuel injection system... Don't laugh !

I would have to disagree. I am VERY impressed with the Bosch system. It supplies so much fuel it's now illegal to use them. Dont forget, this system was used on Ferrari and Rolls Royce too! It's only drawback is poor fuel economy.

Why you may ask ? I would put it to you that the main advantages you would gain come from the fact that you could have your own throttle plate maufactured to your own desired size, to handle the more air-flow required of a higher peak power output at higher RPM, and the fact that you could choose your own capacity fuel injectors to meet these demands, as they're all linked to a common fuel rail loop, and timed to open at varying time intervals, depending throttle position, rpm, air -temp etc etc. via the ECU, which I dare say could be easily(?) modified or mapped rather to suit.

You are not going to find a fuel system more adjustable in terms of getting more fuel than the CIS-E. All these sensors you mention above are a part of this system and can be manipulated. 

Another alternative is the "Ma Gee "(?) EFI set up that actually lets you set up your air fuel ratio in real-time as your driving along, with LED display that lets you know in "real-time" what's going on mixture wise at any rpm, load, and throttle position etc. Perhaps a "hybrid" combination of the two is the go ?

CIS-E is already a "hybrid" combination of mechanical and electrical fuel injection. The only time things need to be manipulated is at WOT (Wide open throttle). Anything in between is just cruising and should be left alone.

At the end of the day, this type of injection system will let you determine your own volumetric efficieny (cylinder filling potential), at any rpm, as compared to the CISE system that limits this by having an Air sensor flap (restrictor!) connected to the plunger in your fuel distributer, that lives above your throttle plate.( This system by design gives a progressive cylinder filling ability) This limits the amount of air available to your cylinders, particularly at lower rpms, as you have a "see-saw" effect occuring between the flap and plunger, regardless of throttle position as it's the engines increased negative pressure (within each cylinder that grows with increased rpm ) that pulls this "air flap" down further, allows more air in, and also moves the plunger in the fuel distributor to deliver more fuel through the never closing injectors. It's a great system, but limited, especially for outright performance increases.

I'd have to disagree. Yes fuel injection is more percice in terms of metering fuel, however the CIS-E is FAR smoother in terms of acceloration than ANY fuel injected engine. The feel of a 560, Rolls Royce, Ferrari or Lamborghini using the CIS-E is like no other in terms of how it revs up. The limits I feel are more or less with the aluminum block and heads.

The air metering dish that is attached to an armature to increse the pressure of the fuel distributor via the "plunger" you speak of is quite straight forward. Operating at nearly 90 PSI pressure means you have LOTS of fuel on tap. The trick is forcing that plunger upwards faster, of course that would require the additional air being FORCED in at the same time to maintain an optimal fuel to air ratio. Did I mention that nitrous comes out of the bottle at 1800 PSI? Of course its regulated down, but even if you were to port in a big shot nitrous kit after the air meter that kit would supply it's own fuel, and then of course you have your dry kit that would be forcing that plate down much faster thus applying more pressure to the fuel distributor plunger to give the extra fuel needed. You also have a crude vacuum that is created when the nitrous passes over an orifice that just happens to be connected to the fuel regulator keeping that sucker closed as not to send any of that precious fuel back to the tank. All things told I think you would be at risk of braking the main webbing's of the aluminum block from the sheer power before you ran out of fuel with the CIS-E. You see when your getting 500+ HP that kind of force is literally trying to throw that crankshaft out the back of the engine. The weak link therfore is NOT the CIS-E, its the aluminum block. At least in terms of forced induction anyway.

Also, with regards to balancing your piston/rod assemblies, it's actually easily done with the use of electronic scales that are suitably calibrated,-( or any type of "scales" as long as they're accurate and can sustain the components weight ). All you need to do (after numbering each assy.) is to weigh each piston / rod assy, note the reading of the lightest one, and then bring the weights down of the others by carefully grinding away excess metal from the lower "pad" provide on the bearing cap. When the weights are all equal, the assembly is optimised by being lighter overall, equalized, and you've removed an enormous amount of bearing load (in Nm) that increases linearly as the rpms go up. Your engine will have even more improved reliability.

Simply weight matching your pistons, rods, pins, bearings and rings is NOT what makes for a balanced engine. The crankshaft has to be run out on a balancer, with the exact weight of your match piston assemblies attached. Much like how a wheel is balanced, the crankshaft also has to be balanced, using Malory (welding) to add weight and drilling to remove weight. Simply weight matching the piston assemblies is only half the job. The crankshaft must also be balanced, and it must be done with special weights attached to the journals that are equal to the weight of your matched piston assemblies. Dont forget, your flywheel and balancer must also be attached when the crankshaft gets balanced. This is why many people are clueless when it comes to the REAL cost associated in balancing an engine the right way.

Cheers,

Rastus


 



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I've always wondered why all these Benzworld guys who are on this massive quest for additional horsepower, don't just say "screw it" and throw in a 100-shot kit for perhaps $1-1.5K.

Instead you have the likes of ManBoobs McClare spending $12K+ on 40 "net HP", and the motor still not running right or dynoing.

Yes, with ElRogo and ManBoobs as my guides, my de-ASRing *facepalm* should go just swimmingly :)


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Hey SELLC,

I had no idea until now that you've magaed to get 500 bhp from your 117, awesome man !!! I probably should have asked ( or guessed rather ) that you had already found the engines limitations, and I sincerely thank you for the info. I honestly thought that the CISE system may have it's limitations in the performance world, not to be critical at all of it's design, ( I've always thought of it as almost perfect, just because of it's simple mechanical workings), yet I based my post on the obsevation that the same engines ( way back in 1975 or so ) actually lost a few horses with K-Jetronic fitted, when compared to the out-going Bosch D Jetronic injection. Enough said...

Also, you're absolutely correct with the balancing procedures ( & the expense involved ) to have this done correctly. I believe the method you've quoted is the "dynamic" type of balancing, and not too many places have the ability to do this, ( at least in my neck of the woods here "Down Under" ). I only offered this "static" type approach of balancing for those who have their motors apart, and might be able to improve on something simply and cheaply from home. I don't know how the Benz factory goes about their balancing "in-house" now-days, but the cranks were ground to a 1 gram to 40mm tolerance "once upon a time", to pass through to the production line, and machined surfaces were within a 3/1000th of a mm consistancy...Also, 1 in every 10 engines were pulled off the assembly-line, and subjected to a number of tests, including Maximum power operation for up to 200 hrs....

Talk about strict quality control, but it does ensure consistancy in subsequent days of manufacture ! And as owners of these cars, you get piece of mind !

Gerryvz, I haven't forgotten about you or your posts, and I wish I had the cash-flow to "enhance" my Benz like you guys have, and I'm taking on-board all of your approaches, and I have to agree, that Nitrous is probably the best "bang for your buck", especially knowing that your car is still running reliably after all these years since fitting it and racing it.

Thanks a whole heap guys, and speak again soon !

Cheers,

Rastus

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Rastus wrote:

Hey SELLC,

I had no idea until now that you've magaed to get 500 bhp from your 117, awesome man !!! I probably should have asked ( or guessed rather ) that you had already found the engines limitations,


 I should mention that I have NEVER had an M117 @ 500 HP, rather 260 + 100 worth of Nitrous (Rated dry jets). The webbing issue at higher than 500+ horsepower does not come from my own personal experiences, rather that of my machine shop who has seen this problem with other customers engines. Of course it is my goal to test this claim, but right now in this economy I stay busy fixing vehicles with much less time spent having fun racing as in my past days.

Just wanted to clear that up. I have however put 400 HP worth of nitrous to a 280 HP Ford 302 engine with a dual stage dry/wet kit and that cast iron engine took the HP without issue or fault. Will an aluminum M117 take that kind of power? We shall soon find out, however it's important to realize that even the aluminum version of GM's LS engines are known to buckle in the 500+ HP arena, thus people are getting into buying the cast iron versions of the LS blocks that are found in trucks and SUVs when HP output gets above the 500+ mark.

Of course new technology allows for amazing things.



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FAR BEYOND DRIVEN

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Hey guys,

It sounds like we're all feeling the pinch of a lack-lustre economy, and I for one haven't really had my hands under-the-bonnet so to speak for quite a while, except to change and flush the oil in my new(?) Benz...I might as well come out and let you know that it's quite a nice 350SLC from way back in 1973....I made this desicion based on the fact that my Dad (and older brother) have owned Benzes all their lives ( Dad still owns a 280SLC that he bought in 1980. It's done over 320,000 k's and honestly still runs like a dream, and it also wins the odd award from time to time at club events etc.) and the fact that I did my apprenticeship at a Benz dealership as a mechanic many years ago...Right about the time when 560's in whatever guise were brand new...

Yeah, I was probably always going to go for a 560 SL, or SEC, depending on availability and cost, but after being able to source not too many in "fair for age and price condition", I had to start looking for something else, and simply couldn't believe how cheap the asking prices were for the SLC's when compared to the SL's. Some of the SL's I looked at were complete bombs, whilst the SLC's were at least 30-40% cheaper in outlay, with more to choose from, and in much much better condition comparitavely. Being over 6ft tall, the extra headroom and longer seat tract makes for a much more comfortable car to drive for a man of my dimensions. (It's a shame that there's no 500SLC's here in Oz, because they are the pick of the bunch...)

I've only ever owned V-8's, usually of the larger capacities, (5.0ltrs & over), and decided on the smaller Benz V-8 simply because of the facts written in my blurb ages ago,where I'm sure I stated that the 450 engine came into being because the 350 was robbed of all it's power etc etc. This is true, and being in my early 40's now, I have been lucky(?) enough to have been able to drive in my time, both the "pre-pollution" vehicles, and the later emmision compliant ones and well, what can I say, in standard trim, the "pre-pollution "cars go heaps harder ! But ultimately, having owned and loved the bigger V-8's since forever, I wanted a small one because I like revs, and the little Benz V-8's rev like you wouldn't believe, even at legal speed limit's,(eg, 3,600rpm @ 70mph, and 5,000rpm @ 100mph with the std 3.46 :1 diff, & top speed is a geuine 124 mph @ 6,000rpm) so now hopefully speeding ticket consumption will reduce....Yeah right !! The thing that swayed me was that afriend of mine bought a 380SL about 6-months ago, and asked me to check it out etc. etc. And I was really surprised at how tractable and user- friendly the car actually was. I really didn't expect this result or even half the response I got from the little engine ! The 4-speed auto & diff ratio help big-time here...

I'm not going to say that the 350 is the best and you've got to have one, because it isn't ! In fact I really miss the "grunt" of the larger V-8, but the Benz motor is quite a sweet running thing, and actually impresses me with the way it goes about it's business - never ever any fuss. It does everything that my 5.0 ltr can do, (top speed included *200 +km/ph or 125mph), only it takes a little longer to get there. Don't forget though, that you guys never got to get a "pre-pollution" Benz V-8 in any guise, as your emmision laws we're enforced well before you could enjoy them, so you might not completely understand where I'm comming from, but that's OK. ( Possibly the the 6.3 was available for you "pre -pollution", and maybe actually the last of the 108's...I'm not sure...Better ask Ralf Nader...)

The big picture is this, I no longer have the law on my back, I'm saving heaps on fuel, I still have a "fun" going V-8, and I've got a car that's absolutely drop-dead gorgeous ! Apparently the car is capable of a 15.9 in the 1/4, and by the formula that I've posted, this result does equal what the factory claim as it's 200 odd Hp @ 5,800rpm.I still have my old 5.0 ltr, and it's capable of 13.8 in the 1/4 mile,( without nitrous either guys , but it only weighs 1350 Kg) so fortune and time allowing, I may just turn this into a Race Car only for the drag strip, as everythings there and running, all I need is a trailer and someting to tow the bastard to the track with !! Ha ha..Well see...And if this wasn't a Benz site , I'd tell you what lives under the bonnet...

Thanks guys and cheers,

Rastus



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gerryvz wrote:
You are right on with your assessment of RSJ. He is best worth ignoring and only referencing indirectly, not in a direct way. RSJ is not worthy of direct conversation from anyone on this board, with the possible exception of his pal PowerStroker.

Cheers man !

HEY GAYRRY ...................... R U TALKIN SHIT ABOUT MY SWEETHEART ****STOMA**** ???????????? HOW DARE YOU !!!!!!!!! FUCKWAD !!!!!!!!!!!!!!!!!!!! AHAHAHAHAHAHAHAHAHAHA !!!!!!!!!!

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stomette wrote:

HEY GAYRRY ...................... R U TALKIN SHIT ABOUT MY SWEETHEART ****STOMA**** ???????????? HOW DARE YOU !!!!!!!!! FUCKWAD !!!!!!!!!!!!!!!!!!!! AHAHAHAHAHAHAHAHAHAHA !!!!!!!!!!


 Quaint how she stands up for her "man" -- LOL !! yawn



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FAR BEYOND DRIVEN

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Hey guys,

I hope "Stmtt" hasn't put you off placing some more posts up here ! I do appreciate the last few posts from you folks, obviousely you've weighed up the cost-factors for a number of improvements that are possible, and realized the best way to go, all be it with a "chance" involved as to how your motors will handle the Nitrous, and have done yourselves proud in the process, especially after 10 odd years of continued use, race wins, and motors that still run very well ! I thought however that maybe when the time comes for a freshen-up of your internals, you might be swamped with a number of choices to make, and these can make things complicated when a final choice is made about what combination of components will offer you the best results for investment made etc etc. I'm not going to go on like a sales brochure and say do this or that, that's your choice as it will be your money ! However I might throw some light on possible piston choices, only from an advantage of design-type point of view that you may benifit from when the time comes...

Obviously, you have a multiple of choices to look at and consider from a number of makers, and material types, eg,- standard OEM replacements, Hyperuetctic, Forged etc.etc. ( I might point out here that the standard Merc pistons are forged, and Hyperutectic...) However, these already fine standard pistons are designed with a compromise inherant to them, namely to enhance emmision output etc. - and usually in the way of a dished piston crown to lower static compression ratio. Enhancing the compression ratio is where I was going to take this post, as the performance improvement happens right accross the rev-range, and in other areas also....

1) Flat - top type pistons offer no restriction to the incomming air/fuel mixture.

2) Flat - top pistons expose the minimum amount of surface area to the hot burning mixture. ( Picture domed and dished pistons, their surface area is larger...)

3) Re- item 2, this means that the flat - top piston absorbs less heat, and therefore has to dissipate less heat through the rings, and to the oil when compared to other piston types.

4) This results in a cooler running engine, and more energy being transmitted to the crankshaft.

5) Flat-top pistons can be made lighter, resulting in reduced vibration and stress.

6) Optimum or desired compression ratio can be obtained.- ( usually by the height of the piston crown to block height at TDC ).

7) Optimized static engine capacity, - eg. Domed piston crowns reduce cylinder capacity, though increase compression ratio, whilst dished piston crowns increase cylinder capacity,
but they reduce compression ratio.

So anyway people, there goes some more " food for thought ", and incase your wondering what figure to aim for, apparently you can go as high as 12:1, before things start having a reverse effect, but if your car is still going to be your daily driver, 9.5:1 - 10:1 willkeep you running fine as long as you use 98 Ron fuel, to be safe though, aim for 9.5:1.

Cheers,

Rastus






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FAR BEYOND DRIVEN

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Hey SELLC,

I was just thinking about your last post(S), and kind-of got to thinking that with the recourses you have, why you haven't yet considered building up an older M100 engine type with the cast-iron-alloy cylinder blocks for racing ? Surely you could be able to source & then modify perhaps a 6.9ltr engine with the dry-sump, & place it into a more modern 126 - type chassis without too much trouble or fuss ? I would almost bet my balls that you could get the 500+ Bhp at the rear wheels with God-knows how much Torque & reliability. I realize that component or ancilliary replacement parts are expensive for this motor, ( eg water pumps cost around $ 1000:00, though they are rebuildable for less etc etc ) when compared to the M117, but 417 cubes + the cast iron block ought to bring the $ per Hp equation into viable consideration yes ? The thought of a 6.9 SEC sort of makes me toss & turn at night with little rest in my slumber....It would be a remarkable achievement world-wide to read about such a post on this sight, with a say 12:00second 1/4 time (or less) whilst smokin' rubber the whole length of the track...Could this be a possible build or are there too many negatives outweighing this sort of project with these expectations ? I would like to hear your thoughts or insights...Oh yeah, the 6.9 comes out with K-jetronic fuel injection which is very very similar to CISE, so your fueling shouldn't be an issue with Nitrous ?

Cheers,

Rastus

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Rastaman,

I have owned three M100 motors/cars (rebuilt one 6.3-liter M100.981 engine from scratch in my garage) and there are quite a number of resons why thy are not good candidates for modding. The M100.985 (6.9 liter) in US trim was only 250 horsepower and in Euro trim 279 HP. The US model had 8:1 compression and the Euro versions were only 9:1 or slightly more. You'd have to custom fab pistons to bump compression as a baseline.

Furthermore these motors are not well designed in terms of their breathing characteristics. So while they have displacement, they were not designed to be particularly high performance. I know folks who have installed 6.9s into the R107 chassis -- it's not an easy install. One hindrance is the 12-quart oil tank which is in the right passenger fender on the 6.9 sedan. That would have to be relocated and that would incolve a bit of custom fabbing on a 126.

FAR better to just take an M119 out to 6.0 or 6.2 liters, or a 12-cylinder M120 out to 7.2 or 7.4 liters. These are quad-cam designs with variable-timing intake cams, and have much better breathing characteristics. It would be rather easy to get 500 HP+ from the V12 and the components are more easily available (though expensive). There are very few of the M100 engines left these days.

Hope this helps, mate. I have tons of experience & knowledge on M100s so would be happy to be an adviser if you choose to go that route. But my advice would be to go with a more modern engine rather than the 1950s & 1960s technology M100 engines.

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FAR BEYOND DRIVEN

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Yo gerryvz,

You gentlemen are really "in-tune" so to speak, as you've been there before....I dare say that you've potentially saved me a lot of time, effort, cash, and heart-ache...Not sure where to go from here except to start saving some money !!!! I thought maybe with the (yes) very old cast-iron block, and the obvious Cube increase might be what was needed from the reliability point of view with the compromise that's set at around the 500bhp mark with the ally M117. I guess when the website read ( W126 & 107's) 1979 onwards, I just thought that that's where you guys were drawing a line from, as from the benefits of your own experiences from models from that year group onwards bla bla bla...I also thought that I might have been speaking with really-young-folks, and not older pros that have been doing this for time-out-of-mind, and well beyond this humbled mechanics own experiences.

I've actually driven a number of 6.9's ( though no 6.3's, but rumour down this way has always held that the 6.3 performed better... ), and nearly bought one once, as the law was just starting to give me more than the normal road-stop liscence check hassles bla bla bla, but I found that my little 5.0ltre V-8 Commodore had better outright performance, so I didn't buy the 6.9, as it would have been a move backwards as far as performance goes, though not by too much.- ( the 6.9 has faster top speed, but the Commodore is much quicker). In case you didn't know, our little Cast Iron Aussie V-8 was manufactured for about 30 years, and actually evolved quite nicely over the time-frame, being introduced in 1969 as a "253"cid engine,(4.2ltr), and then growing balls a couple of years later into a "308"cid (5.0ltr) motor. It finished up being a genuine 5.7ltr OEM engine by the time of it's demise, and the aftermarket guy's could stretch this out to the "King Kong" 6.3 ltr capacity...It's been claimed to be able to produce over 650 hp in 5.7 ltr form, unblown and on 98 Ron Gas. The design was "all-new" at it's release, but it's basically a hybrid in design of your beloved Chevrolet small-block, and the Chrysler/Dodge Hemi designs. Should you want more information about these motors, I'm happy to provide, but there would be hardly any benefit to you or anyone else, except to say that we had our own good thing once, and plenty of them to play around with ! They're still quite a very popular engine to modify as the aftermarket supply of parts is almost never ending, and still evolving. And like your Chevrolet small-blocks, you can build up a complete Holden V-8, without using a single genuine Holden part...

This is why it's so good to speak with you guys, because Australia hasn't developed as rapidly as the States with regards to enhancing Benz Engines ( not like you folks any-how...), they're still very much a niche - market, and their quantities are a lot less here than Stateside. This means that there's a lot less people such as yourselves down here doing what you do.

I sincerely value your experiences that you post up here, ( And so should all who read these posts), and I look forward to hearing from you again !!!


Cheers,

Rasus

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FAR BEYOND DRIVEN

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Yo Guys,

I've been doing some searching about the legalities of fitting a "Dry Kit" to either of my 2 cars, and the answers are always a definitive no-go, with legal implications that would keep a lawyer struggling to keep up with the mess for at least a month ! Back in the early 1990's there were loop-holes that you could work with, but nothing anymore. Even if I could cheekily find, fit, and use a kit, there would be no-where available to provide re-fills, without doing it illegaly, and would cause hassels for more people than it should...It looks like I have to go back to mechanical type methods, to get the extra performance.

One thing I want to ask though, is what about using / substituting a 100% pure oxygen bottle to feed the motor, as surely a similar to Nitrous kit could be used, and perhaps some new loop-holes could be created ?....Sure it would be a similar set-up (the same), essentially doing the same thing, but why has no-body considered this ? You can't be producing anywhere near the pollutants as Nitrous does as your using Oxygen only. Are the fuel mixture ratios the problem as the air that we breathe only has about 23% Oxygen in it and I would be using a 100% mix ? Probably I should think these questions through myself before I post this, as I might end up looking pretty stupid, but if you don't ask, you don't know...

Cheers,

Rastus

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FAR BEYOND DRIVEN

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Yo guys,

I've been looking around on the net for somebody who makes custom exhaust extractors / headers for our V-8 Mercedes, but it seems that there's nobody who advertises their services for our cars. Do you guys know of anyone who can make up a set of tri-y's, or 4-into-1 pipes to suit my baby V-8 in my C107 ? I'm sure that your well aware of the performance enhancement potential to be realised by fitting these items along with a free flowing exhaust system, and I'm certainly keen to source and purchase the said items if they can be found. I know that there's not much room at all between the chassis and cylinder bank, steering box and pitman arm clearance,(not to mention the starter motor), but without doubt in my mind, if even a short 4 into 1 arrangement that directs the waste-gas-slug away from the other cylinders and sraight down the big-bore pipe is much better then the standard manifold, as it's basically a straight length of pipe with the cylinder branches feeding straight into it. This leads inevitably to increased backpressure and pumping losses (not to mention excess heat and cylinder dilution of contaminants as the cylinder will retain more waste gasses). Hoping that you can be compass and set me in the right direction !

Cheers,

Rastus

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Rastafarian

I have a friend in my old hometown of Portland, Oregon who owns & daily drives 5 or 6 different 300SEL 6.3s. If I remember correctly, he had 1-2 sets of custom headers made up for a couple of his 6.3s. I could find out where he had them done. I think it was in the Portland area.

Are you Down Under? Because if so, you should really talk to Franz over at Big Toys (I think it's www.big-toys.net or something like that). The guys is in Australia and is totally mad about M-100 engines. He can do anything you want him to, and he offers some cool custom stuff too.

This page ought to keep you going for a while: http://www.big-toys.net/merc.html

Cheers !



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FAR BEYOND DRIVEN

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Yo gerryvz,

Your a man of good resources ! I know of a guy in Melbourne (Oz) who would be happy to make something up, however he needs the time and the car etc, for an unknown amount of time etc., as it would be done in those moments when the workshops not busy, so this could mean anything from a week to 3-months ! The "Big toys" website was of some help, however they indicated a similar situation with regards to needing the car etc. This would be like you having to travel to California and waiting for things to happen ! I'll keep searching, and will find something out there I'm sure. There's no doubt somebody who can do it or maybe even has it all sitting on the shelf ! Many thanks once again guys and speak soon.

Cheers,

Rastus

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Just when I thought the two faggots gayrry and Rex were bad enough........ Rastus joins in for a sausagefest threesome!!!!! Fuckin faaaaaaaags!!!!!!!! Hahhahahahahhahahahahhahahahhahah!!!!!!!!!!!!!!!!

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LIKE A PHOENIX RISING FROM THE ASHES.................... HERE TO SHIT ON REX!!!!!!!!!!!!!!!



FAR BEYOND DRIVEN

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Hey folks,

I guess you were right when you mentioned that RJS's IQ was lucky to be several multiples of the average Jap engines power output....He's obviousely getting saucages confused with exhaust extractor primary-pipes or something...Maybe it's something in his own diet that makes him think(?) like this, or maybe he just speaks what's on his mind...Which is a worry for sure..."He probably should have taken that left back at Albuquerque"...

I've been doing some research with regards to "Custom Exhaust Extractor Design", and should anyone be interested in how to go about providing for your engines requirements, this is the deal that you should be aiming for, as it will provide the best benefits for your cash outlay.....

1) For engines of 3.5 to 4.0 ltrs, the primary pipe needs to be 1&1/2" to 1&5/8" diameter...Lenghts will depend on the type of cam being used...A good "road cam" ( say single pattern 30/70 ) will need about 70-72" before secondry pipe join...a half race cam ( say a dual pattern 36/80, 82/33 ) will need about 76-78"... and a full race cam ( say a dual pattern 50/76, 82/49 ) will need 80- 84" before joining into the single pipe, that should be at least 18'' long and of 2&1/4, to 2&1/2" diameter before joining into a free flowing muffler...

2) For engines between 4.0 to 5.5ltrs, a similar system as far as pipe lenghts can be used, however, pipe diameter must increase...primary pipes need to be 1&11/16" to 1&13/16", with a tail-pipe diameter of 3 to 3 & 1/2" diameter...

3) For the larger engines, 5.5 to 7.0ltrs, yet another increase in pipe size is called for... Primaries should be 1&3/4 to 2.0" diameter, and the tail-pipe diameter up to 3&1/2 - 4.0" diameter...

4) Obviousely we cannot strictly follow these requirements or figures quoted due to space limitations found in our vehicles....But at least with this guide, we know what to aim for and can go for as large as possible pipes, without hopefully too much compromise...In these instances, think"Volume per lenght of pipe"...eg., if you can't fit the approx. required diameter pipe, go for a longer lenght pipe, with a smaller diameter, as the "volume" of this section of piping will calculate out the same when you get the lenght right....It's all about how well your exhaust can freely direct the waste gasses away at WOT & Max. RPM...

5) Make sure that the muffler exit pipe is at least as large (diameter ) as as the entry pipe...

6) Manufacturers compromise exhaust system designs as they have noise level requirements to address, and also by just the nature of combustion engines, they know that it's easier to empty a cylinder of waste gas under pressure than to fill it...

7) The unusual firing sequence of all V-8 engines dictates that it's almost impossible ( if not practical ) to have all the cylinder pipes joining together at an even 180 degree firing sequence as this means pipes having to join together from cylinder bank to bank. A 4 into 1 type system ( per bank of cylinders ) at least directs the waste gasses away from the other cylinders preventing back-pressure rises and cylinder dilution, though shock-wave extracting is compromised due to the uneven firing sequence within each bank...

8) The purpose of the "cross-over" pipe is to provide the communication of exhaust pulses between the banks of cylinders due to the unique firing sequences experienced with the dual-plane crankshafts utilised in most V-8's.

9) The "tri-y" exhaust extractors typically are used due to space limitations, and offer far better flow than standard manifolds or headers, and should be considered for use when the 4 into 1 system connot be fitted. Only a little power loss is experienced when compared to 4 into 1 systems.

10) The improvements to be found by going to all this trouble are quite amazing, as some people have found up to 60hp just by fitting a good exhaust system alone from a factory spec. standard engine... Improvements in fuel economy in cruise mode are also to be experienced as less throttle effort is required due to a cleaner cylinder...eg. You don't need more air and fuel to overcome residual waste gas left behind in the cylinder to to a restricted exhaust system..

That's probably all I can handle for now, & I hope this is written in an easy to digest way, and if there are any questions for where I haven't elaborated nough, don't hesitate to ask !

Cheers,

Rastus

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FAR BEYOND DRIVEN

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Yo folks,

I thought it might be of some benefit to further go on with exhaust system designs and concepts, as it's one thing to say "you should do this and that", and another to think about why....

1) All the exhaust gasses when allowed to escape from your cylinder via the exhaust valve and port, have several measurable qualities about them. They have volume, heat, speed, waste energy, sound, particulate quantity, and a tendancy of natural movement from a high-pressure(heat) to a low-pressure (cool atmosphere at your tail-pipe).

2) Volume of course varies depending on throttle position and RPM. The info in the last post is considered optimum for the engine sizes as listed at WOT and Max. RPM.

3) Heat is naturally given off and is Waste Energy. Due to an engines design characteristics, this cannot be harnessed in any-way if the possible Max. HP requirements are to be met at High RPM's. Turbo-chargers are the only exception to this fact, and they have their own problems that are Not part of this post.

4) Speed of the waste gasses is a quality that also varies due to a number of factors, not least of which is actual engine RPM and load. This is where the actual pipe diameters and lenghts come more-so into play...The actual purpose of Extractors is to primarily direct each "exhaust gas slug" away from the cylinder as straight and directly as possible whilst retaining some residual heat so as to not allow too much temperature differential at the exhaust valve itself, as this causes vale failure...The second feature is to provide enough length before the secondary pipes downstream, so as not to interact with and pressurise other exhaust port outlets, as this will prevent cylinder contamination. The third feature is a theoretical possibility, of where the passing of one exhaust-slug into the common "collector"-pipe ( and out the remaining pipe system to atmosphere ), creates a low-pressure in the remaining primrary pipes, thus enhancing the "extracting" of the exhaust gasses in the other cylinders that have as yet not purged their waste...This possibility is also why a "cross-over pipe" in a V-8 is recommended, as it allows all 8 cylinders to communicate with one-another, in an at least even, sequential manner, as to how the firing sequence has occurred, so as the engine sees itself as an evenly displaced/firing 8 cylinder unit, and not an uneven 2x 4 cylinder...eg, During the moments of Valve-overlap, the air just outside your air cleaner housing ( at atmospheric pressure), is in "direct communication" with the exhaust slug entering the atmosphere, at your tail-pipe exit...Pipe diameters, lengths, and straightness all affect how well these exhaust slugs are allowed to escape at their own speed. Any obstruction to reduce this exit speed leads to back-pressure, and this reduces exhaust output and power.

5) OEM engineers (and aftermarket camshaft designers/engineers), work with all these variables trying to find a Balance between waste-energy, and required power outputs at required Max RPM;s, Cruise speeds, and sitting at traffic-lights idling. This is NOT EASY and trade-offs will always exist, just due to the way a combustion engine is.

6) Sound energy ( waste energy also in another form other than heat ) is absorbed of-course by your mufflers/silencers (and all the exhaust pipe-length). Mufflers are like a cork, as even the (recommended) "Straight - through fibre-glass type" allow the exhaust slugs to Expand within themselves, and absorb bulk of the sound energy and heat, and convert it into more heat within the muffler body. It's this gas expansion and heat-transfer that reduces the sound energy, therefore lowering db's at/out your tail-pipe. Because the expanded exhaust slug now has to contract again at the muffler outlet, a reverberation effect now occurs within you muffler that's the beginning of back-pressure ( or the reverse-flowing of your engines gasses ), and gradually rises as RPM rises, meaning that your piston now has to start pushing the waste gas out the cylinder...A good exhaust will/can minimise this effect to some amount, but whilst we "Have to use muffflers of some sort", back-pressure will rise at least to some amount, and our extracting efforts will deminish as a result. Measured exhaust back-pressure readings on some factoryOEM American vehicles have been measured at over 5-Bar, whilst a good performance enhanced exhaust carefully designed, can reduce this figure to less than 1-Bar, and still be under the EPA's required 83(?)db noise limit...Some OEM exhaust pressures measure well over 5-Bar....

7) Particulate quantity is a variable typically associated with mixture quality, engine efficiency / ( condition), temperature, fuel quality and driver habbits. An exhaust system will only retain them for a little while and then expell them....- ( hopefully ).

8) The natural movement of the gasses has already been touched on earlier with regards to Valve overlap, and how the atmospheric air pressure at your air claener inlet is in DIRECT COMMUNICATION with the exhaust slug exiting your tail-pipe into the atmosphere. A free-flowing exhaust system can possibly enhance this movement of "gasses" to the point where this can have an almost "supercharging effect" occuring as the combination of extractors and exhaust take advantage of the 'momentum' present of these moving gas-slugs, thus creating an enhanced negative pressure at the exhaust port, that will ehance exhaust "scavenging", and thus cylinder filling of fresh air/fuel mixture.

There was some more stuff that I was going to go on with, but I've had enough for now, and I hope all this helps everyone in their thoughts...

Cheers,

Rastus

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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together".    Dwight D.Eisenhower.



FAR BEYOND DRIVEN

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Yo Guys,

Over here in Oz we have a manufacture of oil additves etc. going by the name of Nulon. They have a product on the market (amongst many others ) going by the name of E-30. This is basically a PTFE engine oil additive very similar (if not the same ) to Slick-50. Lots of people say all these types of additives are crap and to nothing but rob you of your hard earned cash etc. I write this post confidently and very honestly to say that this particular additive works, with some amazing results...

Let me start by saying that I only bought this product because Slick-50 is very hard to find nowdays, especially down this way, but I have used it before, and at present I have and have owned a Suzuki RF-900R sportsbike since about 1996, in which case I added the Slick-50 to it way back in 1996. It's so far done 176,000 kilometers without me having to touch the engine at all, still runs fine, does not drink oil or blow any smoke, and is still capable very easily of climing to its indicated 275 km/ph...The original timing chain is still fitted, along with the original clutch...No problems of concern are yet in sight, and the bike always gets a good dose of WOT on an every-ride basis, once everything is nice and warm, after about 20 k's of riding. I also own and enjoy a 1991 GSXR-1100M, that I bought about 5-years ago, and it's going fine having added Slick-50 to it.

I was always happy with my little 350SLC, if a little disappointed with the lack of grunt from the motor due to the lack of cubes etc. The work that I do now involves going away to sea for sometimes months at a time, and so I was looking for a way to preserve and protect the internals of my little V-8. When I couldn't source any Slick-50, I had no choice but to buy/try Nulons E-30. The bottle reads that it's safe to use in motorcycles with wet clutches etc. So me being me, bought 2x500ml bottles of the stuff (@ $40:00 each ), and added it to my motor before I went away. I bought 2 bottles because the Mercs as you all know hold about 8 ltrs of oil, which is nearly double the capacity of most cars engine sumps etc.
So what about the results you may ask ? In one word, AMAZING.

The SLC is a completely different car to drive. Where in the past it would hold it's own in top gear climing steep gradient hills at highway speeds where I live, it now accelerates up them, no bull. I have also changed ALL the fluids in the car, and whilst at it, bought a syringe from the local chemist (drug-store ), and added about 50ml to the diff, 50ml to the transmission, the same to the powersteering, with the rest of the 2nd bottle going into the motor, with the "dregs" going into the fuel tank ! The car is a completely different beast to drive, and I'm honestly not dissappointed with it's performance at all anymore, as it happily pulls the car along very easily now, where as in the past, you'have to go for a lot more throttle to get it to move faster. The best way to describe this experience to you, is that it's like how your car behaves when your on holiday, and your doing a lot of miles, and after your 2nd tank of fuel, your car just wants to get up and go and roar !

I wouldn't write any of this to discredit myself or undermine anyones intelligence, but if your not using a product like this in your own vehicle, your missing out on a lot cheap and easy performance, not to mention enhance wear protection for a l o n g time. The bottle reads that it will last up to 80,000k's in your motor, even after successive oil changes etc., so I know and am completely convinced that it's a cheap and now proven friction reducing product. You won't necessarily notice it when you initially put it in, but the next time you go for a drive, I assure you all that you WILL BE AMAZED at the transformation. Almost free horsepower ! Not to mention that all the subtle"funny" running noises will nearly all dissappear.

I hope that you folks don't interperit this post as an advertisement for "another one of these products " as I'm most definetily not doing this, I'm just a very happy owner of an old SLC that's had it's performance completely transformed, and I honestly believe that your missing out BIG-TIME if you don't buy and put this stuff in anything in your car that holds oil
or has to pump oil or something around. I'll probaly buy some more and put some in with the wheel bearings when the discs need replacing. Also, these hills that I mentioned earlier, where the car used to automatically de accelerate going down them with a closed throttle ( this was only subtle de-acceleration ), I now have to apply the brakes as she speeds up now. The car doesn't actually go any faster at top speed, as it always got to it's 205 km/ph, but I would have to say that it would get there now more quickly and easier. Also, I've had to drop my idle speed by a couple of hunded revs as it climed from a steady 750 rpm in gear to about 900rpm, - enough said !

Cheers,

Rastus






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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together".    Dwight D.Eisenhower.



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HEY RASTA...................... WHAT SORTA ASSTRALIAN ARE YA???????? NO ONE GIVES A FLYIN FUCK ABOUT WHAT YOU SAY CUZ U DUNNO SHIAAAAAAAAAAAAAAAAAAAAAAAT!!!!!!!!!!!! AHAHAHAHAHHAHAHAHAHAHHAHAHAHAHAHAHHAHAHA!!!!!!!!!!!!!!!! GO BOB ON A KANGAROOS DICK BIAAAAAAAAAAAAAAAATCH................................. CHEERS MATIE!!!!!!!!!!!! AHAHAHHAHAHAHAHAHAHAHHAHAHAHAHAHAHHAHAHAHAHAHAH!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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FAR BEYOND DRIVEN

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Yo folks,

I have to say that RSJ may give a damn, as he replied(?) once again in his no-brain, no-sense manner ! I was initially a little concerned as to RSJ's mental state of mind, as seems to know a lot about qt "saucage three-somes"..., but when it comes to buggery with animals, serious questions must be raised about a lot of things, especially the fact that he is a member on this site....Whoa, what's the world comming too ? Lucky it's not my problem....I think that maybe we all have to reconsider reducing the amount of IQ given to him to much less than several multiples of a Jap engines output ! And maybe a visit to a mental-health practitioner....Or it's possibly too late already I think...

I have to appologize to the other folks on this site, as I was warned about replying, or even acknowledging the presence of RSJ, but when someone needs help, you can't just ignore them can you ? I've also been looking around for info on camshafts for our beasts, or at least info for people to think about when they decide to go out and buy one etc., and it's quite a lot to put into perspective actually, but I think I can make things a little easier for people understand, but the biggest problem is being specific about the facts, and the facts for one engine vary from one engine make to another...However, since most people that run V-8's have the OHV pushrod type engines, there are some consistencies with these engine types as to being assured of making a "good" choice, and getting your value for your bucks for your cam selection !

I'll finish by saying that an engines camshaft is the single most governing factor determining the characteristics of the engine as a whole...You basically build everything else in the car from the design characteristic of this component... Very important stuff !

Cheers,

Rastus

__________________

"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together".    Dwight D.Eisenhower.



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GET A WOMAN, BIAAAAAAAAAAAAAATCH!!!!!!!!!!!!! NOTICE NO ONE GIVES A FLYIN ASSTRALIAN FUCK WHAT YOU SAY!!!!!!!!!!!!!!!! I FELL ASLEEP TWICE READIN THROUGH YOUR LONG ASS REPLIES!!!!!!!!!!!!!!!

SUCK MY CAWK, MATEY!!!!!!!!!!!!!!!!!!!!!!!!! CHEERS OR IS IT CHEERIO???????????????? AHAHAHAHAHAHAHHAHAHAHAHAHAHAH!!!!!!!!!!!!!!!!!!!!!!!

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Rastus wrote:

Yo folks,

There is absolutely no easy way in one small post on this site to inform people out there about performance camshaft-selection and design, as every different 4-stroke engine working in the real-world has its own in-build design faults, that cam-manufacturers (and car manufacturers ) have to over-come individually, depending on the engine being considered for such a modification. Some engines utilize hydraulic camshafts with hydraulic lifters, others have overhead-cam designs, and others still ( especially now in modern times ) use double overhead camshaft designs, that are the ultimate for performance, as valve-overlap can be easily adjusted/modified to suit power-output in desired specific RPM ranges... ( More on this a little further down the page...).

Yeah, it's called Electronic Variable Valve Timing although every manufacturer has come up with their own unique way of saying the same thing. It's proof that technology, through evolution, is the mother of all horsepower. I'm green head to toe when it comes to going faster for less. LOL!

In finishing....The fitting of ROLLER ROCKERS is probably the first place to start improving the performance of any OHV V-8 that uses push-rods, as the benefits of these items probably need me to write another page of blurb, and I'm not goin to do that today ! I do hope that if you've taken the time to read through all of this info, that you've gained a little more insight and confidence in dealing with the huge world of camshafts. Regarding our beloved Mercedes Benz engines, what can I say, I know mine already revs to 6,500 rpm, so I'd say it's already been sorted out by the factory!

In the case of a Mercedes-Benz engine you would need a "Roller Follower" which I have said SEVERAL times would no doubt increase horespower and performance drastically. I am unaware of ANY roller follower for the 560 SOHC engine. No doubt anyone who produced a set with a slightly larger ratio and a roller wheel in the center to "ride" the camshaft would sell more than just a few sets. HOWEVER it may become necessary to harden the camshaft and modify the lobe for optimal performance as often times OHV (I call them under head cam engines or Pushrod engines) will have drastically different camshaft designs from a flat tappet cam and a hardened more round roller cam. Thus it's going to take more than some punk over on BW with access to a CNC to make some sort of kit up. I'd imagine the cost of such things would make buying a DOHC M117 seem relatively inexpensive.



 



-- Edited by SELLC on Thursday 23rd of August 2012 12:23:41 PM

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FAR BEYOND DRIVEN

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Posts: 3845
Date:

Yo folks,

There is absolutely no easy way in one small post on this site to inform people out there about performance camshaft-selection and design, as every different 4-stroke engine working in the real-world has its own in-build design faults, that cam-manufacturers (and car manufacturers ) have to over-come individually, depending on the engine being considered for such a modification. Some engines utilize hydraulic camshafts with hydraulic lifters, others have overhead-cam designs, and others still ( especially now in modern times ) use double overhead camshaft designs, that are the ultimate for performance, as valve-overlap can be easily adjusted/modified to suit power-output in desired specific RPM ranges... ( More on this a little further down the page...).

Probably the best way to go about choosing a performance camshaft for your engine, is to find out what the current specifications are of the cam living in your engine at the moment, and then deciding where you would actually like to see more improvement in your engines out-put. I'm going to base this post from the point of view that you'll be thinking about replacing the camshaft by itself only, with no other mods to the valve-train or cylinder-heads, and improving engine-output for an otherwise standard vehicle only, not for an all-out race car, as this involves very major modifications to every part of the car...

Why do you need to know the specs of the cam living in your motor ???

By knowing these specs., you can then decide whether the cam your thinking of buying is actually going to improve your power out-put to where you want it or not, by comparing it's specification against what you already have.

What are the specifications and what do they mean ???

There are normally 3 specifications regarding camshafts that need to be understood, so that you can make an educated calculation as to the performance enhancement to be gained. These 3 variables all effect one another, and power output, depending on their given values, and it's very tricky to picture in your mind what's actually going on with regards to the gas-flow improvement potential. These specifications are known as Lift, Duration, and Valve- Event Timing.

* Lift = Valve lift is measured in (U.S.A.) thousandths of an inch, and is the maximum distance the valve is lifted off its seat.
* Duration = Valve open duration is the length of time, measured in crankshaft degrees/rotation, that the valve is open.
* Valve Event Timing = The positions of the crankshaft at the point where the valves are considered open, or closed.

Of these 3 major design "yard-sticks", Duration is certainly the most well known among performance enthusiasts. This is due to the straight-forward manner in which Duration affects power-output. Fundumentally we can say that, within reasonable limits, the longer the valves are held open, particularly the intake valve, the more top-end power the engine will produce. However....If valve duration is increased beyond a certain point, additional top-end power will be produced at the expense of low-end performance. In Racing applications, top-end power is virtually all that counts, but for a high performance street-machine, drivability and low-speed torque are just as important....eg. There's no "real-world gain" in being able to make 40 or 50 extra hp at 6,500 rpm, if the guy next to you gets 2-3 car lenghts on you "off-the-line" with his extra 40 ft/lb's of torque at 2,000 rpm...

Finding the optimum Valve-lift can be an asset in producing horse-power because it can add power without substancially affecting low-speed performance...In theory, the answer appears simple...eg. Design a cam with short valve-open duration to maximize low-end power, and very high lift to give top-end power...However, valve-train mechanics are never this simple, and in this scenario, the high valve acceleration rates ( from open to closed ) developed by profiles like these, substancially reduce valve train reliability by increasing loads/stresses ( not to mention vibrations and harmonics...) on springs and every other valve-train component etc., and inevidably increases valve-guide wear... Generally speaking, camshaft manufacturers "blend" a complimentary amount of duration, for the required/desired amount of valve-lift, so as to provide reasonable longevity of all valve train components when carefully matched together. This is why "cam packages" are often recommended for long term reliability and enjoyment...Also, it is GENERALLY considered that about 1/2'' valve lift for all road-going OHV V-8's to be thought of as the "rough" maximum, if long-term reliability is a major considerstion. (This is a huge variable depending on your brand of engine...but not an unreasonable yard-stick either, as you can always extend your duration and event-timing to make up for this short-fall !).

When the the intake valve is opened "early", and the exhaust valve is closed "late", ( Relatively speaking with piston at TDC beginning its intake stroke ), there is a period of time when both valves are open. This is called "valve-overlap", and its effect, called "scavenging" harnesses the moving mass of exhaust flow (as a sort of vacuum cleaner), to draw out residual burnt gasses and initiate induction flow. How long the valves are held open together, is a built in dynamic, directly related to either the duration, and/or the Lobe Centre Angle (LCA) of the camshaft design. With lift and duration remaining unchanged, it can be generally stated that, the more valve overlap present, the higher the peak power out-put of the motor will be experienced, at the expence of low-down power and torque.... The same spec. cam with LESS valve overlap, will make less peak power, but have a much wider power-band, provide better fuel consumption due to better manifold vacuum, and will be a much more managable engine to control on a driving day - to - day basis. The "valve - events" usually provided on the cam card when you buy one, will allow you to calculate just how much valve-overlap exists in your camshaft selection.

Selecting a "performance" camshaft should begin by making 2 important decisions...

1 Determine the main operating power range of the engine.

2 Determine how long the camshaft must survive...

The importance of No2 is especially relevant when choosing a solid or hydraulic flat-tappet cam, particularly for performance applications involving the ever-popular "small-block" Chevy, and several other high rpm V-8 engines. There are so many different manufacturers out there, and so many years now of development, that it would be pretty hard to make a "bad" choice. Ask people "in the know" about your engine, and what they have to say about particular camshafts, and then base your decision on some of the facts written above, as hopefully now you can understand what they'll be talking to you about. Also, as a very GENERAL guide, I've decided to post up a selection criteria with some numbers so you can have a more informed perspective on camshaft selection...

FOR STREET USAGE

* Maximum engine speeds should be kept below 6,500 rpm.
* Valve lift should not exceed approx. 0.500-inch.
* Cams with 270 - 285 degrees of intake valve duration are suitable for High Performance street / strip applications.
* Once valve-overlap exceeds approx. 40-50 degrees, all power gains are achieved at the loss of low down torque, and idle quality will begin to suffer, meaning poor
starting and running when the engine is cold.

FOR RACE APPLICATIONS

* Maximum engine speeds may exceed 9,500 rpm.
* Valve lift will be approx. 0.550-inch for track usage, and up to 0.650-inch for pure competion, Maximum HP requirements.
* Cams with 285 - 295 degrees of intake valve duration are suited for "mild" race engines, say up to 7,500 rpm.
* Cams over 295 degrees are generally best for all-out competition.

Also, optimum power in any racing effort can ONLY be obtained when intake manifold volume, header tubing size, "carburettor" air-flow ( and number of barrels ), compression ratio,combustion chamber design, port configuration, and many other variables are evaluated in a careful testing program.

My personal experience has shown that almost all the different camshaft manufacturers make a particular and VERY SIMILARLY SPEC'd camshaft that's suitable for supercharged and/or turbocharged vehicles. They're typically a "split-duration", dual-pattern cam having "around" 295 - 300 degrees duration, "around" 0.500-inch lift, and around 70-75-degrees overlap... But at 0.050-inch valve lift, ( this is the measured lift required of hydraulic grinds where the measurable flow of gasses actually starts to happen ), the intake valve will then have a calculated 224 degrees duration, and the exhaust valve will have 234 degrees duration. (Hence the term "split duration"). These cams work more than fine in naturally aspirated engines, and I would "advise"(?) anyone in doubt about what to use, to fit one of these spec'd babies, as the more than satisfactory results that I have recieved from fitting the said cam to my 5.0 ltr V-8 were, and still are very, very, impressive. Incredible throttle response... Awesome agressive mid-range acceleration with a singing top-end...And with minimal loss of low-down torque and power...

In finishing....The fitting of ROLLER ROCKERS is probably the first place to start improving the performance of any OHV V-8 that uses push-rods, as the benefits of these items probably need me to write another page of blurb, and I'm not goin to do that today ! I do hope that if you've taken the time to read through all of this info, that you've gained a little more insight and confidence in dealing with the huge world of camshafts. Regarding our beloved Mercedes Benz engines, what can I say, I know mine already revs to 6,500 rpm, so I'd say it's already been sorted out by the factory!

Cheers,

Rastus
















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"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together".    Dwight D.Eisenhower.



FAR BEYOND DRIVEN

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Hey SELLC,

I would probably be among the first people to buy a set of "Roller Rockers" for my Benz ! What a great suggestion ! I also thought that I should briefly mention that as good as having a Roller Follower for the Camshaft would be, to gain the extra "rocker ratio" you mentioned, you would have to introduce a "Roller Tip" to where the rocker would then "roll" over the valve tip locator, to get a subtle improvement. ( It has been approximated that potentially a 6 degree increase in duration is to be expected...). This spacer / rocker locater is also the "valve-rotating" element for our engines. Also, to increase Rocker arm ratio more substancially on these motors, you would actually have to move and relocate the cam-bearing towers outboardboard, away from the vee on both banks, to get the exra leverage from the rocker that your suggesting...There's possibly other ways, but this way would maybe let you use the current rocker fitted, a no-doubt limited amount. Probably much better to re-grind the cam to how you'd like it.

I also thought that you might like to know ( if you didn't already ) that our M116 & M117 engines were originally design wise considered for "shim under bucket", direct valve actuation by the cam, but the idea was shelved due to believe it or not, American "Clean Air" regulations that stated that an engine should require minimum maintenance, and maintain correct emmission out-put for at least its first 50,000 miles. At this point in time, the Shim under bucket design was considered too much of a risk to this requirement, as if it didn't need re-adjustment at this milage, it would need it very soon afterwards. Also, it was thought that the amount of workshops nation-wide, would not be capable of performing such a specialized, and time consuming maintenance task, so we (happily) got adjustable rockers/tappets initially, followed by the maintenance free "hydraulic compensating elements" as fitted to your 560. Another thought was to go with "Timing Belt Drive" for the Camshaft, but once again, belt life back then was considered way too short, and we got "Duplex Roller Chains" instead. I can't stress enough about how gratefull I am about having a chain instead of a belt !!!

Also with regards to my last post on camshafts, it's probably worth mentioning to people that although there are heaps of cams to choose from, caution is needed before you buy, as you never know what the actual capacity was of the "test-mule" engine, or selected computer program etc etc. What I mean is that in the case of the cast-iron small-block Chevvies, they came out in more varied capacities than any other engine make I can think of, and yet the cam you buy for it, will fit all these differing engines, but behave differently in each one. Generally speaking, the larger the engine, the tighter the LCA ( or "bigger" cam) you can afford to go, and achieve the targets you aimed for. So don't ever take the Power - Ranges the cam-card says for granted, as the "same" cam will behave differently from a smaller capacity engine to a larger one, and you'll miss your power output in the RPM range you hoped for. And if you have an Automatic transmission fitted to your car and don't know the stall-speed of the Torque convertor, it would be better to keep to less than the 285-degrees duration as mentioned in my last post. It gets quite complicated doesn't it ?

Cheers,

Rastus

__________________

"Only an alert & knowledgeable citizenry can compel the proper meshing of the huge industrial & military machinery of defense with our peaceful methods & goals, so that security & liberty may prosper together".    Dwight D.Eisenhower.

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