Vomit

Actually, just the gears. I noticed this weekend at Carlsbad that the C32 is geared really shiiity for the 1/4 mile run. The problem is that 3rd peaks out at 95? or so MPH, and then you end up doing the last part of the 1/4 in the low part of 4th. I mean, where does the stock 4th gear top out at. . . 140 MPH or so? And it's not like I'm ever going to top out in 5th, unless I find out that I have terminal brain cancer and I decide to take a few fellow motorists with me in a dying blaze of "glory."

It would be really nice to change the gearing so that 6000 RPM in 4th was showing 117 or so on the speedo. With this mod, I think that a stage I C32 has the possibility of running with supercharged E55s and Z06 vettes in the 1/4 (with slicks, at least).

Anyone out there know whether a rear-end gear swap is possible, at what expense, and whether this causes problems with the skid control or any other aspect of the car (other than gas mileage)?

430

While you are wishing for new gearing, which would be nice. I am wishing for an LSD. Now if we could both get what we wanted in one nice, low cost package.

James F. Cannon

If you are having traction problems now, increasing the gear ratio will only make the traction problem worse. You could go from 3.07 to 3.27:1 I believe, but you will be increasing the torque to the rear wheels. This might not be a problem if you can get stickier tires or improve your launch technique. I have a similar issue with my car in that if I let it shift itself it does so just before the finish line. If I hold it in third gear, my ET and MPH improve but I hit my rev limiter. Makes me wonder if I should consider replacing my 2.82:1 with the 2.65:1 ratio if possible.
I personally don't think LSD is necessary on these cars but I'm no expert!

Zeppelin

Vomit - One problem with a lower rear end gears is that now you will be pulling more RPM while cruising on the freeway. It currently turns 3000rpm at 80mph. You may be running 4000rpm at 80mph depending on the gear.

James - An LSD will do very little in the 1/4 mile, although with the current ESP system the brakes are being applied to each rear wheel in order for it to keep from spinning the one. Who knows how much horsepower this eats up. An LSD is definitely needed for turning left and right, like on a track.

BenzoAMGpower

thing with the C32 is u cant hold the gear at redline... it shifts by itself... somebody please correct me if im wrong!!!

SJT03CLK

You're correct.

cscollis

I dont think you are correct. When I launch in 1 it stays in 1 until I hit 6200 rpms then shift or manually shift it to second no matter the amount of throttle.

When at the track turn off traction control put it in first and hammer it. It will stay in 1st until 6200 then 2nd to 6200 and so on.

If you put it in drive the tranny will choose your gear but if you tap it it holds the gear.

If you mean bang the rev limiter you are correct! MB wont let you!

CynCarvin32

Vomit,

3rd actually ends around 106 mph and fourth ends around the mid to high 130's (did not do that much lol).

The car actually has good gearing IMHO and any lower of a rear end would make launching a real mess. Remember 245's are very narrow for 360 ft/lb of tq.

As for running with E55k's and Z-06's? I hightly doubt it. Not enough power and no where near the torque. The C32 with 450 hp is about equal to a E55 but it still has 60 ft/lb of torque for you cant get away from the fact that you are modding a 3.2L motor. The MKB C32 with 472 hp still was slower in the 1/4 mile than a stock E55. 12.1 - 12.3 on a Stage I seems wishful. Stage III? Maybe

C32 is fast..faster than an M3 but not quite a E55. 516 ft/lb of tq is ALOT

430

How about not changing the entire rear end. Just getting shorter 3rd and 4th. Of course good luck finding someone to actually make the gears.

Vomit

3rd peaks at 106? I thought it was lower, but I've never checked it carefully (too busy looking for cops). Well, then maybe I need to go the opposite way, and put a taller rear end it, with the idea of finishing the 1/4 in 3rd. I just want to avoid doing the last portion of the 1/4 in the bottom of 4th gear.

I think that the C32 4th peaks at more like 149 MPH. Assuming that my speedo is correct, I held it in 4th on the freeway today and was running 70 MPH at 3000 RPMs. This would translate into about 149 MPH at 6200 RPMs. Anyone know the exact MPH figures for redline 3rd and 4th in the C32?

I swore off LSD right after the C32 Chernobyl post, but it would be nice to have both wheels spinning.

As for the C32 v. E55 issue, all I have to say is: Ye of little faith, I vow to eventually kill a supercharged E55 (granted, the E55 may be on the back of a towtruck at the time)

CynCarvin32

If you can beat an E55 I will bow down!

I need to go to the strip sometime. Let me know if you watn to run a very unexperienced E55 driver (at dragging -- never learned to launch the C32 and well the E55 is even worse! -- i work on making her turn!) I would also like to see my E500 run against a stock C32 for its shorter 2nd and 3rd gears keep her moving quickly. Funny thing is that first in the 7 speed is the same for the 5 and 7 speed. Why not make first shorter than 39 mph?

as for top of 3rd in the C32...106 is the exact figure (that was the highest gear I could run through without having visions of jail cells and body bags). I forget about 4th however (did it once). Look for the C32 review in Car and Driver from 2002. I had the speeds for each gear as I recall. You could be correct for 5th gear really is an overdrive gear. I wish 4th were not so tall being that this would fill a gap in the rev band...who needs fuel consumption gains?

BenzoAMGpower

i meant you cant hold the gear at redline.. that at a certain RPM it shifts to 2nd by itself even if you are in 1st....and so on!!!! I mean it wont let you bang the rev limiter!! :p But ive driven my cousins C32 a few times and thats what ive found with the car!!

CynCarvin32

and those are $$$$ to change!

The rear end simply changes the overal ratio of ALL the gears not just one or two specific gears.

3.06 works well with the C32. But yes, 4th is a bit long winded!

cincyc32

Vermit,

Check out: http://bergwerks.com/different.jsp

430

C32 Chernobyl post? I am searching but not finding anything.

Zeppelin

3rd gear tops out at 106mph? That's funny because all my dyno charts show 100mph where it shifts to 4th, then 4th gear goes to 140mph. Oh well it probably just shifts early.

Zeppelin

You spent all that time trying to make the C32 handle, now your trying to do the same with the heavier E55? Best of luck .

BenzoAMGpower

want a 4dr MB that handles... get a C55!!! Want a conservative and fun to tune little street car... get a C32!! Got some dough to spend and want some brute power...get an E55!!! Big baller?...get a Maybach!!!

CynCarvin32

Stand corrected (Road and Track Test)

1s = 38
2nd = 64
3rd = 100
4th = 141
5th = 178


Im doing well but thanks for the well wishes and your blessings for good luck.

It's not what you drive its how you drive. My slightly modded (stock motor) C32 gave many sports cars a serious run for their money.

Learn how a car works and it can be driven hard. My days of dumping 6k into a car are done for now. When I want a fun car and a daily car I will put money into the fun/canyon/track car. But the current cars in the garage will be left alone.

The E55 is a barge and yes it understeers but I personally say it does less plowing than a C32 did stock. After a day of driving I can still read who made my tires and what size they were before the sidewall wore off -- more than you could say for my C32! Funny what OEM negative camber can do for a car! My E500 is the best of them both...for its fairly neutral and has no issues being asked to pick up its skirt and get going. Trouble is when you get that E500 going, the brakes leave town and forget what to do at stop signs (she came to a hault but not very willingly).

Vomit

O.K., it's war. . .

"Vomin" then "Vermit"

Next thing you know you'll call me "Quayle."

BenzoAMGpower

how bout "Hurl"???

Vomit

I'm trying to get my wife ("Wretch") to do some posts too.

Vomit

So the stock rear end is a 3.06? If I want the 4th to 5th shift to happen around 120 MPH, then I would need something in the 3.55 range, correct? Anyone know where I can get these gears, and how much? Cincy: I checked the Berg site, and they don't seem to offer differentials for the 203. Anywhere else?

James F. Cannon

Vomit
I am not sure but I believe the W208 CLK would be the same differential. You should call Bergwerks to verify this. You could also call RENNtech and I am sure they could provide you with what you are looking for if price isn't a big issue.

CynCarvin32

I would call MKB or RENNtech first . The guys in Van Nuys are a little sketchy if you ask me. A friend had some servicing and susupension work done there and the failed to let him know his rear control arm was bent and that the car would not allign to factory spec. This is all in a 1k charge to replace all the rear bushings!


The next step up in a diff for a MB is a 3.46 and this will push your shift point for 3-4 to around the high 120's.

Trouble is this stuff is extremely expensive. Once you change the diff. all the electronics need to be re-programed for the speedo, and all other systems read the driveline for vehicle speed, trans shift points and mile counting.

Good luck.

Maybe a Stage II upgrade could get you going faster for less money. A diff upgrade will be around 5k for a MB