C32 AMG, C55 AMG (W203) 2001 - 2007

C32: tail becomes unstable under heavy braking

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Old 09-11-2005, 02:30 PM
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C32: tail becomes unstable under heavy braking

I just got a C32 with a lot of mods. The handling mods includes, H&R springs, Bilstien shocks, uprated anti-roll bar and 18" S-03 tires. I just found the car very hard to maneuver in high speed turn. When I drive at 220kph on a straight section of the hiway, approaching a wide turn, I would hit the brake hard to slow down to 150kph before I enter the turn. I would trail brake as I enter the turn, but at this time the tail will become very unstable and begin to walk sideway. It's not drifting yet and there's no tire squeaking. The more I turn the steering as I approach the apex, the more I feel the tail walk. I always fear the tail will eventually snap so I will always delay my turn in to allow for more time to brake and I will end up missing the apex.

I never had this fear with the Mitsu Evo. Is this the nature of C32? Is there problem with my suspension mod??
Old 09-11-2005, 02:49 PM
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C32
Why are still braking in the turns? All cars will have the tailend become light under braking. The C32 is only evil under heavy braking when the car is put into "dyno" mode with all ABS/ESP off.
Old 09-11-2005, 03:08 PM
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Originally Posted by Zeppelin
Why are still braking in the turns? All cars will have the tailend become light under braking.
This is what I normally do:
1) First, I apply maximum braking before the turn.
2) Gradually reduce braking and start to turn steering, as the car approach the turn.
3) Once into the turn, foot off the brake and ease on the throttle.
4) Start to increase the thorttle after the apex.
5) Maximum thorttle exiting the turn.


Step 2) is where I fear the tail might snap.
Old 09-11-2005, 06:12 PM
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2005 Obsidian Black C230 Komp Sports Sedan, 2006 Iridium Silver ML350 SUV
the split of second after heaving breaking, all the weight transform to the front of the car, therefore the force lift up the rear, it is possible to feel the car is unstable if the car is turning too much..
side note, if you wanna break loose, thats the time you wanna go fulll throttle!
Old 09-11-2005, 07:05 PM
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Originally Posted by raywong@hkstar.
I just got a C32 with a lot of mods. The handling mods includes, H&R springs, Bilstien shocks, uprated anti-roll bar and 18" S-03 tires. I just found the car very hard to maneuver in high speed turn. When I drive at 220kph on a straight section of the hiway, approaching a wide turn, I would hit the brake hard to slow down to 150kph before I enter the turn. I would trail brake as I enter the turn, but at this time the tail will become very unstable and begin to walk sideway. It's not drifting yet and there's no tire squeaking. The more I turn the steering as I approach the apex, the more I feel the tail walk. I always fear the tail will eventually snap so I will always delay my turn in to allow for more time to brake and I will end up missing the apex.

I never had this fear with the Mitsu Evo. Is this the nature of C32? Is there problem with my suspension mod??
Trail braking is the quickest way through any corner but each car responds differently to this activity. A C32's rear suspension as a lot of rubber bushings and I think this makes the car unstable under heavy braking.

The point of trail braking is to make the car turn in quicker and more completely so the feeling of the rear wanting to step out shows that the is turning in quickly. That really is what you are looking to have happen so next time just try to ease of the brake a little sooner and more smoothly. The transition from brake to gas is very important and a smooth and quick foot could help with this issue.

The camber chagne of the wheels as the car goes from braking to gas could be an issue and that is where these rubber bushigns and their deflection could come into play. Replacing all the rear links with heli joints would eliminate the play and make the car far more stable in such activities.

hope this helped
Old 09-11-2005, 09:56 PM
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How many miles do you have on the rear tires?

Look at them very carefully. If the car is lowered, tires will be worn on the inside very quickly.
Old 09-11-2005, 10:01 PM
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2002 C32 Black/Charcoal
Originally Posted by raywong@hkstar.
When I drive at 220kph on a straight section of the hiway, approaching a wide turn, I would hit the brake hard to slow down to 150kph before I enter the turn.
Let me get this right. . . you are attempting to brake from 125 MPH to 95 MPH in a turn and are surprised that the car is unhappy with you???? Dudemon, lay off the crack.
Old 09-11-2005, 10:08 PM
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Actually, I think you are supposed to barely tap the brake before you apply any type of braking to align the pad and the rotor for better braking power and stability.
Old 09-11-2005, 11:52 PM
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I thought C32 supposed to understeer. My Mitsu Evo 7 can never oversteer when entering a turn too hot, even with maximum weight transfer to the front.

I can still make the C32 understeer if I go around and around in circle, increasing speed gradually, the front eventually break loss. There's no weight transfer in this case.

My tires are 80% new, pressure is F36/R34.
Old 09-12-2005, 02:47 AM
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996 C4, previously owned 996 c2, c32 amg, 350z, R33 GTR, R34 GTR
I think you will not be able to drive the C32 in the same way as the EVO, the c32 is too soft to take quick direction changes and feel planted aqt the same time. Better to slow your corner entry speed by 10mph and use the bottom end torque to pull you out.
Old 09-12-2005, 02:55 AM
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Evo = AWD.
Nuff said.
Old 09-12-2005, 07:02 AM
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I know Awd let me step on gas sooner when exiting the turn. I just don't understand why I have to slow down the C32 so much when entering the turn. I used to enter a turn at 150kph everynight with the Evo, now I enter with the C32 at 120kph and the tail still feels unstable.

I tried my friend's stock E46M3 at the same turn same speed(210kph slow down to 130kph and enter). His tail was a lot more stable during the braking and the initial turn in.
Old 09-12-2005, 10:23 AM
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It's not the car, it's your suspension mods.
Old 09-12-2005, 10:43 AM
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What specific shocks are you running? What is the diameter and make of the rear bar?

The rear bushings provide a lot of play in the suspension and under heavy braking wiggle way too much. The car gets light and starts shaking. This is repeatable every lap from 140mph to 90mph turn entry. Trail braking must be used with caution in the C32. If you engage dyno mode, things get much worse when trail braking and the car will snap around without notice.
Old 09-12-2005, 12:14 PM
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Originally Posted by smgC32
The rear bushings provide a lot of play in the suspension and under heavy braking wiggle way too much. The car gets light and starts shaking. This is repeatable every lap from 140mph to 90mph turn entry. Trail braking must be used with caution in the C32. If you engage dyno mode, things get much worse when trail braking and the car will snap around without notice.
This sound exactly like what I am experiencing! I feel better I am not alone. I search the ex-owner's post and found this:
"...So I decided to have Bilstein stocks and H&R springs installed...
Does the C320 H&R springs (part number 29392)fit for C32 AMG?...I noticed the rear is too low and I added one more spring pad 10mm for the rear..."

Is this set up ok?
Old 09-12-2005, 09:21 PM
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I am not aware of any Bilstein damper set available for the W203 series except for the PSS-9/Carlsson which is not available through Bilstein NA. Are you sure you have Bilstein? Could you possibly have Bilstein inserts within the stock Sachs bodies? What are you spring rates. Most aftermarket springs have too high a rate for the rear spring. Go back to the stock swaybars. You don't really need anything thicker than the AMG bars. And it is easy to go way to thick on the rear bar.

What is the measurement from the fender lips, front and rear, to the center of the hub. I have found a good compromise for track and street to be 13.25-13.50" in the front, and 12.50-13.00" in the rear. This will allow the front to clear concrete parking stops and steep driveways and still provide for better handling and looks. Go much lower and you will blow your front struts and not necessarily increase handling.
Old 09-13-2005, 04:17 AM
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I just confirm with the ex-owner what he had installed:

Eibach sway bars for front and rear.
H&R springs front and rear.
Bilstien shock for C-Class front and rear(added 10mm pad in rear).

The simplest thing to try is to get the H&R coilover(adjustable height & fixed damping) but keep the sway bar, think that might help?
Old 09-13-2005, 10:04 AM
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Bilstein's North American web site does not list any shocks for the W203. Does he have a part number?

Put the thinest pad in the back to lower the rear. This will level out the car a bit and provide a little less weight transfer to the front under heavy braking. The only thing left to to is a rear sub frame modification.
Old 09-13-2005, 10:47 AM
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You must have imported shocks from Bilstein Germany. Their C32 offerings are the B8 and B12 systems, part numbers 005424/005425 and 105425 respectively. The C320 part numbers also indicate other offerings including the B4 and B6 systems, part numbers 002454 and 005423. These systems vary from high pressure, low pressure, twin tube and mono tube designs. Look on your front struts and rear shocks for the stamped ID number and check against these numbers above for comparison. Bilstein's name should also be stamped on the bodies or have the traditional decal applied.
Old 09-13-2005, 03:12 PM
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2002 C32 AMG
No braking during the turn....

Originally Posted by raywong@hkstar.
This is what I normally do:
1) First, I apply maximum braking before the turn.
2) Gradually reduce braking and start to turn steering, as the car approach the turn.
3) Once into the turn, foot off the brake and ease on the throttle.
4) Start to increase the thorttle after the apex.
5) Maximum thorttle exiting the turn.


Step 2) is where I fear the tail might snap.
Brake before the turn and follow 3,4,and 5 from above. Doing this right takes practice and is different with different cars. My C32 is much different from my 330 or my G35 but after practice I found out what I can and can't do with each car.
Old 09-15-2005, 12:53 AM
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the problem is that this guy is comparing his all wheel drive EVO to a 203 benz. big freakin difference. he needs to understand the rear wheel drive more to really excel.
Old 09-15-2005, 02:50 AM
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Originally Posted by MBHustla858
the problem is that this guy is comparing his all wheel drive EVO to a 203 benz. big freakin difference. he needs to understand the rear wheel drive more to really excel.
I can brake way eariler into a turn in a AWD car.
I can floor the throttle right after the apex in a AWD car.
What good is RWD?

After reading everyone's reply, I conclude that my super thick Eibach rear sway bar is causing the rear to become unstable when trail braking into a turn(weight transfer).
I plan to get some coilover and stock AMG swaybars.
Old 09-15-2005, 05:05 AM
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996 C4, previously owned 996 c2, c32 amg, 350z, R33 GTR, R34 GTR
raywong - rear wheel drive is generally inferior to awd on the road if getting from a to b is what concerns you. You have to balance the car on the throttle from just before the apex. Switch off the esp and learn how to drift.

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