stephens

I am upgrading my E55 to an LSD. I have a choice of staying with 2.65 to 1 or changing to 2.82 or 3.06 to 1 rear axle ratio.
Whilst the thought of a 3.06 to 1 is appealing, I am concerned about traction problems. I know this is a long shot, but are there any SCed MB owners out there who have changed rear axle ratios who can give me some feedback?

fiftyfive4me

I sure hope somebody can help you out on this one, it's about time you "receive" some considering how much valuable information you have "given" to this board. Man, you're a little bit too advance for me when it comes to mods. Take it as a compliment.

good luck!

Bilal

May I ask who is doing the tuning? If it is anyone apart from AMG, you might need an ESP mod. And the higher the axle ratio, the quicker acceleration? Is that how it works? How about some in car vids of your '55.?

Pueo

I'm glad someone else is finally considering a rear end ratio swap!I've been thinking of this same thing for the past year while waiting for my car. Mercedes puts such a small rear ratio on their cars, I don't need to do 200 mph!

I would put the 3.06 ratio in, the 2.82 may not make enough of a difference for you to feel. See if you can get a limited slip rear end with the new ratio at the same time, it'll help traction a bit but you'll still probably melt those tires! Throttle response will feel incredible with the new rear end, I remember putting a 4.56 rear on my 70 Z-28, that was a blast! Not much top end but boy did it ever get there fast!

I hope you do go through with the rear end change, it'll be good to see how much of a change it'll make! A bigger rear end ratio is usually a good " bang for the buck", except that the cost for a Mercedes is a bit high!

E55AMG99

I know this is oversimplification but here's my $.02.

The 2.82 will give you 7% more torque multiplication but also increase your cruising RPMs the same amount. It would be like driving 70 instead of 65. Doesn't sound like much but I suspect gas mileage would suffer by the same amount. The 3.06 is a 15% change and would be like driving 75 instead of 65.

Also, keep in mind that speeds at which the transmission shifts will also be lowered. I've estimated the new shift points below. On the surface, the 3.06 sounds awesome but I wonder what effect it would have in real world driving. I know how good it feels to smash the throttle pedal to the floor and have the car break loose at freeway speeds as it grabs second gear. The 3.06 will give 15% more multiplication but remain in 3rd. If allowed to get into second gear, the car will have 50% more multiplication and put the engine higher up in the power band.

I hope I have not cast too much doubt on the 3.06 gearset becuase I'm contemplating the same thing for my 2004 when it arrives later this year. BTW, does anyone know if AMG will do this for a US bound car at the factory? Both dealers I've talked to had the "Deer in the headlights" look when I asked them about it.

2.65 2.82 3.06
1st 50 46 43
2nd 81 75 69
3rd 127 118 108
4th 155 155 151
5th 155 155 155

stephens

I'm probably doing the ratio change through Vath, it includes the neccesary ECU mods. I decided on the diff upgrade to get LSD fitted. I wouldn't consider it otherwise.
I'm really stuck on this one, because the car will already light up in first at any speed with full throttle acceleration. The SL comes standard with 2.82 as did the W210 E55. I noticed that the US delivery CL55 comes with 2.82, whereas the rest of the world gets 2.65 to 1 along with the S55.

Fuel consumption is not a consideration, but having too much torque for the 285 rears is. Given that I have other mods planned to increasepower to 600hp I'm in a bit of a quandry.

BTW if anyone is interested I finally got hold of a copy of the workshop assembly/disasembly instructions/diagrams for the oilcoolers, chargecoolers etc.

pocholin

If you are doing other mods already I'd stay with 2.82s
If all you were doing was the gears then I'd go with 3.06
How much for the 3.06 with ECU mods?

E55AMG99

600hp? Interesting! Please let us in on your plans.

If all of the power is way up high in the RPM range like my old 911, the lower gearing will help. However, with 600hp on tap, the only thing you'll accomplish with the 15% lower gearing is keeping the tire manufacturers in business!

It sounds like MB is using gearing to fine tune to cars to the different world markets. More speculation here...

Although the W210 is ligher, it does not have the low end grunt of the SC motor hence the lower ratio in the older model.

CL and SL are heavy and need a little more gearing to get it moving.

S is designed more for the luxury market and performance second.

stephens

Thanks!

I realise most people are happy with their cars as they come, but for the few that want more, my aim is to share my experiences to minimize the pain associated with doing things differently.

I know the Germans will say that only AMG or at worst Brabus should touch your car, but for what they actually offer, it just doesn't make sense price wise, even if you could get it. (for alot of the mods they want your car, or at best major parts of it, anyway). If I lived in Germany and I was going to drive my car for hours on end at 250kmh I would probably feel the same way, but I don't and I won't so I feel this advice doesn't apply to me personally. The other real issue is, bluntly I am well off, but I am not filthy rich. There is no way I am going to spend $20K USD to get a 50hp power gain that I believe can be done more effectively for 10% of that amount.

As an example, I have booked another session with Powerchip next week to work on Air/Fuel mapping, as the car runs so rich up top, it eventually sends the ECU into fits of depression. There is obviously plenty of power available through the ECU alone. The upside of this is my experience will then be available to Powerchips customers worldwide. The downside is somebody has to go first and the risk is blowing the engine up.

stephens

There is a choice of ratios, the price is around 4000 euro

Blocktrader

Unless you are going to get more than 285mm of tire in the back, I would go with 2.82's with the power you are going to achieve. This engine has alot of are under the curve, and does not need as much gear as other motors. The engine backs off enough at shifts that I don't know if you will have traction problems there, but you may end up getting shifts too often with the shorter gearing.

Pueo

stephens,

Just curious, where did you hear that the US model CL's are coming with 2.82 gearing? The MB website has the ratio as 2.65 like the E55 and S55, only the SL55 comes with the 2.82 rearend.

Go for the 3.06's, if you look at the calculations that E55AMG99 did on the ratio's, it's not too bad. 151 mph in 4th gear! The 2.82 at 7% wouldn't justify the expense in my opinon, you may as well just stick to the stock ratio and do the other mods first! With your planned increase in hp to 600, you may not need the rearend swap. But then again, with the rearend swap to 3.06 you may not need the hp increase.

stephens

Pueo
The problem with the amount of torque the AMG motor produces is traction. There is no doubt if 315 tyres would fit, I would go for the 3.06 ratio. Right now with 285's and a 2.65 to 1 rear ratio the car will spin at any speed in 1st gear with ESP off. I am concerned that the ratio change may do this in second as well. now it may look impressive, but it doesn't result in very fast acceleration.

As a side note gearing for the US delivery only CL55 is here . The US CLK55 runs 2.82, but the ROW gets 3.06. Go figure..

James F. Cannon

Stephens, the 2.82 gears are in my W210 and as you know my car is supercharged. I also run 285's and traction in first gear is always a problem. On occasion my car has fishtailed when downshifted to second gear under full throttle. If indeed you are going to have 600HP, I would not go any higher than the 2.82 ratio. You may have an annoying harmonic at highway speeds with the engine RPM's increased. Just some thoughts from a fellow enthusiast. Good luck and keep us posted on your results. Hey, maybe you can do better than Treynor in his S600! Let's get the E class back on top!!!

stephens

Thanks, you've pretty much confirmed what I was thinking about the gearing.
As to beating Treynor, I'll give it my best shot, but I gotta say, that S600 is faaaaast.

Pueo

Stephens,

It's interesting that the rearend ratio for the CL55 is different from the AMG website and the MB website. I thought that the CL's came with the 2.65 as most articles in magazines quoted that also. The ROW comes with the 3.06 rear? WOW! How do they control wheelspin on those cars? We need to find someone that can verify the correct rearend ratio.

Am I correct in understanding that the E55 can break the rear loose even after a rolling start, traveling maybe 10-15 mph? Wow, neat! I've got to go down and test drive that E55 that I still have a deposit on.

I understand your concern that traction with the 3.06 would be a problem from a standing start, I just felt that with most street races starting from a rolling start the 3.06 might be helpful. Might be nice to chirp the tires in 3 gears! Haha!! It was fun doing that with my M5.

Excuse me if I seem a little ignorant concerning these high torque MB's, haven't had much time behind the wheel of one! Drove a CL55, damned that was fun, must have scared the crap out of my salesman, his right foot kept looking for the brakes! Not too willing to let me test drive anymore AMG's.

stephens

Pueo
"Am I correct in understanding that the E55 can break the rear loose even after a rolling start, traveling maybe 10-15 mph?"

Try 30-40mph and it still spins!

The CLK55 has 3.06 gearing not the CL. The discrepency with US and ROW CL's is down to a US specific config. The web site I linked was the MB USA AMG site, not the International AMG site.

Ted Baldwin

...............There is someone on this forum with W208 CLK55 with a supercharger and a differential change. I believe it is SLEESTACK. You may wish to contact hime. I believe he used MKB. My understanding is that his car did redline pretty quickly and he was considering going back to the stock differential of 2.87.

.............Since the advent of traction control, I understand that differential chabnges on Mb's has become a bit more cumbersome because you have to reprogram the ESP. Am I correct? If so are there any tunners in the USA that do this other than MKB which is not as well represented in USA copmparted to Kleeman, Brabus, Renntech.


Ted

Ted Baldwin

............here is a link.

LINK


Ted