I run 19" Michelin Pilot Sport Cup 2's on my 2012 Cayman R. I do 5 or 6 DE events a summer usually at Watkins Glen. Manufacturer's recommended maximum cold pressure on the tire is 31psi. I bleed all 4 tires to 35psi immediately after coming off track. Does this sound about right? Should I be using different pressures for front and rear? Responses much appreciated!

 

On track in my gt4 I was running them 32 hot.
Bleed to 32 at end of session right after coming off track

Drive with tpms on screen and during session bleed in hot pits to 31 when getting over 35 as you are killing the tires ( and your lap times)

 

Yes you put way more heat in the tires than you would in the street.

Just remember to put some air in before you drive home. The tires will still be a bit hot so the best you can do is put a 4-count or 5-count in. The goal being not to find your tires 10 pounds under normal cold target the next morning.

 

35psi is about perfect IMO. Apparently Michelin says 33-36, imo better to err slightly on the high side if anything.

 

32-34 psi hot

 

32 or 33 hot.

 

"Optimum" pressures are going to depend on setup. And being a pound or two above or below should not impact lap times by a whole lot for a production car (as opposed to a formula car or sports racer).
In my opinion, a street car setup with smallish tires, softer springs and less camber is likely to be better off a bit on the high side. I've seen both 33-39 psi and 32-36psi as being the spec range for hot pressures for MPSC2. For sure you'll be fine at 35psi.

I'll be at Watkins Glen next Monday/Tuesday with COMSCC I might fiddle with pressures some, but honestly I don't expect to conclude anything, and I'm on Yok A052s anyway...

YMMV as they say, but I've generally gotten decent life and even tire wear for "street/track" cars at the track running at 36. Would have zero qualms about 34, but I wouldn't get caught up in a "how low can I go" approach to hot pressures... I know I'll never get enough track time or be consistent enough to get a real comparison of pressures vs. lap times so just keep it conservatively on the higher side.

0.02...

 

Keep in mind that the Cup 2 has varying profile and rubber composition across its width.

 

You could try tweaking the front / rear pressure a bit and see if you like it. Example 32 F and 33 R. Will make the car mildly more rotatable for example in T9.