SMP

Since all the parts are already available from the CLK63 BS, a trip to the MBZ parts department will take care of those issues. Most cars have cooling problems, and to be fair, the C63 wasn't designed for extensive track use. But with a few modifications, it can be! It's not only engine oil and transmission temperatures that will sore, but power steering and differential (especially with LSD) as well and will endure way more stress and guarantee premature failure without proper cooling. For prolonged track use I highly recommend all those upgrades.

1Lop2K5C

I believe the C63 already has an oil cooler (passenger side), does anyone know if the CLK63 blk has a beefier cooler? Where is the tranny cooler mounted?

fordandford

I thought I would like to share that if you hit the rev cut 3-4 times, the transmission may go into 'limb' mode, ie go to auto mode. As you will be driving the car pretty hard on track, if you do not change gears fast enough on manual, u can hit the rev cut relatively easily especially when you are powering out of corners.

I had the switching of manual into auto mode at first after hitting rev cuts a couple of times. But since then, I have been very careful not to hit the rev cut and never had this issue again. Car works great.

For those with this problem, see if avoiding rev cuts work.

racenut

SMP, yes I agree. Unfortunately, at present Mercedes does not offer any cooling upgrades for C63 in the performance pack (like they did with the last SL55). So best bet would be to research comparable, but more hard core variants (i.e. Black Series), for possible retrofit options.

Fordandford, I did hit the limiter ONLY ONCE very briefly (very sure because afterwards was careful not to do it again) on an upshift coming out of the 2nd gear chicane. But the car was still pulling hard for at least another half of lap (at least 10 manual gear change up AND down) before going into full auto and finally limp mode.

Did you experience the same, or did your tranny went straight to full auto after you hit the rev cut?

ATL_MB

I didn't, really. I just took more frequent breaks to let it cool down. The only suggestion I heard was to put a wrist sweat band on the reservoir to catch the fluid and make sure it didn't spray around and to also keep the front shield on the top of the engine for the same reason. Obviously you don't want fluid on the exhaust.

I would say that the fluid didn't gush out or spray - the amount of fluid made the reservoir (very) wet on the outside, but didn't seem to get far from there, although it dripped down a little. It wasn't like fluid was all over the bottom of the hood or anything. My dealer said they would work on a solution, but I haven't heard anything - I will check back with them.

ATL_MB

Quick poll -- do those of you reporting problems on the track use your air conditioning? I do not use my A/C on the track (windows have to be down anyway) but I see many people who do.

Just curious if this might be a contributing factor (AMG Academy uses A/C the whole time, and that is the only place I have seen this issue first hand).

Brian GT PRO

We have never had an issue.. Temps always stayed in acceptable zones, brakes never faded, no issues whatsoever. Were we easy on the car?? Buttonwillow 2.03 on street tires and stock suspension you be the judge

Case1906

I did lose the manual shifting at Summit Point, but late in the last session on a very hot day. This occurred while down shifting and under heavy breaking. This unsettled me more than the car. It happened only once and I've run the track a number of times. Have not experience limp mode in the C63.

I did the AMG Challenge at Homestead in 2009 and experienced limp mode on the banking in a CLS 63. My initial thought was "damn, I broke their car. I'm in trouble....."

I'm thinking limp mode induces the loss of the manual shifting, but clearly not the other way around.

SlowinFastout

i have been on the Nordschleife with my stock C63 - no problems at all.

Oil Temps went over 120°C and i've always been in "M" Mode with the tranny.

Outside temps were around 35°C !

Go see here: http://www.youtube.com/watch?v=mAnfKhXBgd4

Carac

Transmission radiator is in the center with the primary radiator. Steering radiator is on the right, where the non-functional vent is on the C63.

NickZag

I've never had any issue's with anything overheating, even on a tight track slower track like Infineon on a 93 degree day.

Case1906

No, I would not think to use AC while on the track. I'm a green racer, looking to conserve fuel.

jvanbrecht

And by conserve fuel.. you mean 6mpg rather then 4mpg I got with my AC on at Summit point... it was sooooo hot that day.. (Hyperfest 2010)20 min on the Jefferson track put me at 4.5mpg.. but a fun 4.5

Oh.. and even with the AC on, power loss was minimal, not enough to prevent me from eating up the suburu's on the track.. although the lotus's destroyed me, I doubt turning off the AC would have made a difference though since its a short small track with a bunch of turns.