[CSBM5]

Originally Posted by Pete_vB

First, expect compound to be changed per Chevy's specs, so you can't assume it's the same as every other Sport Cup 2. Second, you can work heat into the tire over time. Just driving down the highway at freeway speed will raise the temp perhaps 15 degrees, then once you start pushing it you'll build heat quickly. The skidpad is the best possible place to put heat in.

That said, it's been low 50s, occasionally low 40s in my area in the morning recently, and I pull car out of the garage to head to work every morning... with TC off. I can guarantee that at 43F I will spin the tires up in 2nd in a straight line when I floor it, quite possibly 3rd too. However if I was running a skidpad I'm sure I could work heat into them to get good grip. If it rains at that temperature, however, and you've got water cooling the tires... forget it.

Yes, that's true about compounding as Michelin does company specific compounds and even tread patterns for various tires for OEMs. Are you running PSC2 as every day tires? Using the 245/35 and 265/35-19s? I probably would have put them on the M3 in 255/275 sizes if they had been available last year (used PSS instead).

I'm sure they worked a ton of heat into them on the pad as there is simply no way a tire that is designed to grip at the levels of the PSC2 does not succumb to the physics of temperatures approaching the glass transition temperature of the compound. Heck even the PSS grip is very poor on 45F pavement. In the M3 (DSC off of course) in 1st it will just spin them with throttle, and if you're in 2nd and floor it from say 3k rpms, when it gets to about 5k, they just break loose. I have them on the M5 too, and with all the midrange torque it's impossible to use full throttle in 1st or 2nd in those conditions, and you have to be careful in 3rd.