So I took the 03 CLK 55 out to Sears Point (aka Sonoma or Infineon) for a track day last week. The car was awesome, and I had a blast. My only complaint is the traction control was very intrusive on the high speed turns. I was afraid to turn it off because there is a lot of trouble at Sonoma, and a rare 911 GT3 RS hit the wall and had a lot of damage.

Does anyone know of a way to put the car in track mode, or something similar, or is the system either on all the way or off all the way?

-Mark

You have 3 options. ESP on, where the vehicle will cut power and apply brakes, ESP off, where power is not cut but brakes are still applied, and dyno mode. Dyno mode disables everything including ABS. I personally wouldn't even consider dyno mode an option.

Just curious, what tires were you running? Is your car stock or modded?

I drove my c32 and had my ESP off, and because I couldn't modulate the throttle well I was killing my R888 Toyo's. The power was spinning the rear wheels so easy when coming out of corners, I ended up switching the ESP back on to protect my tires and I actually has faster laps times with the ESP on.

Next time I go to the track I really need to stiffen the car up more so it doesn't roll too much.

My friend, when you disable your ESP you are relying on your own ability to drive the car. At least with ESP on you have a chance of not hitting something on the track. Your best insurance if tracking is going to be in your future is to invest in a Limited Slip Differential, Quaife or Wavetrack. Althought the quaife is good for straight line running there may be issue if extreme cornering is induced as the rear wheel with reduced loading may still spin. Wavetrack on the other hand will possible give you more of a direct positrac feeling while cornering hard. JMHO Others please jump in if I am wrong.

My CLK55 is stock other than AEM dry filters and the upgraded tires & rims that came with it when I bought it. The previous owner put on 19 Pilot Super Sports on OZ 3piece racing Superleggera rims.

My next track event will be at a safer track, so I will probably be able to go without the ESP and see what happens.

I am familiar with the Quaife LSD, but I will have to research the wavetrack.

Thanks for the help!

-mark

Your 2003 CLK55 AMG has the same ESP programming as the C32 AMG. It is different from the the 2005 C55 AMG and presumeably 2005-2006 CLK55 AMG (which is what dre5373 described above).

This is how it works in your 2003 car:
ESP On: Stability control is on, meaning the computer will brake the appropriate wheel and/or cut engine power to correct understeer/oversteer. Traction control is also on, meaning the computer will brake the drive wheel which has excess spinning relative to the other and/or cut engine power to stop excess wheel spinning relative to the other.

ESP "off": Stability control is not completely off.....rather, it allows for a higher understeer/oversteer angle before intervening with braking of the appropriate wheel and/or cut engine power to correct the excess understeer/oversteer. Traction control is COMPLETELY OFF. You are left with a completely open differential. So if you are powering out of a tight corner hard, the inside drive wheel will likely spin excessively, robbing power to the outside wheel (which has more grip) and lead to difficulties accelerating out of tight corners. In this scenario, a mechanical limited slip differential would help.

The difference with the newer C55 AMG (and presumeably 2005-2006 CLK55 AMG) is that there is still an electronic traction control function active with the drive wheels when ESP is turned "off". In this mode, the computer will still brake the inside spinning wheel WITHOUT CUTTING ENGINE POWER, therefore transfering power through the open differential to the outside wheel which has much more grip, mimicking the effects of a limited slip differential and allowing you to lay down the power more effectively coming out of tight corners. BMW calls this function "e-diff" in their cars like the 135i.

Thanks for the correction PC, sorry mt789!

great, that really helps alot. Sounds like i will be ok with ESP off on a fairly fast track, but a tight track, or a track with tight turns like Sonoma (Sears Point/Infineon) I should consider a mechanical LSD. Too bad ther is no way to get the electronic LSD like the newer cars have. I guess I will just have to convince the wife that i need to upgrade to the CLK Black series...

-Mark

Great cut and dry write up. Thank you