Case1906

Tracking my C63 for the first time on Friday ( 2 mile road course)! Would like suggestions for tire pressures from the trackers out there.

NORTH 44 C63

I ran 34lbs (Stone Cold) all around last month. Running 245.40.18F - 265.35.18R P-Zeros for the track.

Ran very neutral and REALLY hooked up.

Thanks to 1stamg for the advice.

dlb000

The simple answer is that the tire pressure listed on the tire's side wall is the recommended pressure by the manufacture. Performance tires list the proper pressure needed (maximum pressure) for driving in performance conditions.

NORTH 44 C63

Hmmm? I respectfully disagree.

The "Max Tire Pressure" shown on all tires is just that. The Max recommended tire inflation pressure when cold. Absolutely no correlation to performance (Gas milage maybe) unless you want poor handling performance and even worse tire wear!!

Recommending to inflate to 50Psi cold (P-Zero Max Inflation Recommendation) is irresponsible and boarders on dangerous advice.

Case1906, do a forum search. There are a number of great posts on this topic. Here is one: https://mbworld.org/forums/c32-amg-c...32-advice.html. Look at post #13 for some great overall advise.


Have fun.

1st amg

Thats funny, I guess you never have tracked a car, if you were to inflate at max as Barry stated, you would kill yourself, and if not every other car on the track around you, wow, people should respond who are familiar with any topic and have experience, rather than trying to make an uneducated guess, btw, I am not bashing you, but just making sure that other members who read this thread dont follow your lead.

Case1906

Thanks North 44 and 1st amg. You are the type of guys that I was looking to hear from. I just disregarded the "simple answer." I've tracked my RX-7 and all the Mazda guys play with pressures to get the best handling.

1st amg

Good luck, you are really going to be impressed with this car on a track, and everyone else attending the event will look and listen to your car in awe.

DFW01E55

Whatever you start at, remember that you will pick up 5 to 7 lbs of pressure during the session.
Given the torque you have, it might help to reduce the rear by 2lbs compared to the front. This should help to minimize oversteer.

CynCarvin32

Having had far too much seat time in a C32 at the track I say starting at 34 cold would be useless. I would have had no sidewall lettering left with that pressure. I think starting in the low 40's and bleeding down as you drive the day will be ideal.

Any street tire needs to be 40 psi or more for track duty. Yes you build up pressure as you drive but 40 warm will will likely be too low given the weight of the car, limited negative camber and propensity to understeer.

I would even go for the reverse stagger with tire pressures. maybe start at 38 front and 36 rear. This could make the car a bit more neutral since all big 4 door cars will want to push when driven hard.

I also need to ask how you drive? If the OP is just doing a track even and not pushing it to the limit all day long less air pressure will work. I have friends who use 35 psi and are just fine for their driving style.

If you plan to be in the advanced group, chasing down track prepped cars go for a cold psi of about 38 and the bleed down as you get over the upper 40's that day. 44-46 hot would be a good number I think.

Case1906

Thanks, I saw your post after the event. I started cold at 36 all around and was 42-44 hot during the day. First time on the track with the C63 so I'm learning the car. Will play around with pressure more the next time.

Car was fun to drive and gets tons (I mean tons) of attention in the paddock. The car is much better than I am, and it took me a while to learn to hustle it on the track.

Had problems early on with braking points at end of 125mph main straight. Just not use to the big brakes. Finally, the M paddle shifters were the way to go. I tried the S automatic during my first session and it seemed to shift (or not shift) at the wrong times on certain parts of the track.