Recommendations?

I was shocked when I got the GT3, that the recommended factory pressures were like 30/33 or something like that. Seemed low but it was explained to me that they are designed to run at those pressures due to stiffer sidewall construction, etc etc.

I was running 36/44 on 19's with my 996 so you can imagine my confusion. The factory knows best though...

These are street pressures of course.

So where do I need to be with 19's for track pressures? cold and hot? I have done a couple track days and have been running cold street pressures more or less. I've been concerned about dropping them and it being too low.

I was with Brian from JRZ this weekend at Sebring. He actually recommended staying with the 19's due to the wheel center and steering geometry. His suggestion, aside from getting JRZ's, was to stick with the 19's and get the best tires I can for the car.

I do need some suggestions for good cold and hot track temps on these 19's.

 

Also really depends on the rubber you are using, weather conditions, time of day and how hard you are pushing that rubber- some tires vary a lot more in cold to hot than others due to their rubber really heating badly and whether or not you are an aggressive driver.

Get it close to factory spec when hot. So go out do a few laps then release pressure as the track day progresses to maintain at factory specs for a start. Then start fiddling depending on what you feel the car is doing.... either way 44 is way too high for track use. You will be sliding everywhere after a lap for sure.

 

No expert here as this car is new to me as well, but I ran 19"MPSC's on HRE comps this weekend. Started cold at 26/29 and had to let air out twice to keep target hot pressure of 34/38 and again on the right side due to clockwise track. I got the hot pressures from another 3 driver who extensively tracks and records pressures and temps and keeps a log.

Interesting cars as there are so many variables and so much divergent info about set ups. Of course the ultimate set up will be when we have enough experience to know what works best for our own style and the particular track. I know I spent 3 sessions really struggling with grip, especially in off camber situations, and then set rear sway to full soft and bingo, the car came alive and I was able to steadily improve speeds and confidence that I was not about to lose the tail all the time.

 

For MPSCs, shoot for 34/35 when hot. Don't go higher unless you like ice.

 

I agree and also same for Corsa System.

Trofeo's will be a bit lower, around 32-33 psi hot.

 

I told you. 26/28 when cold.

 

44 was rear street cold temp.

 

those pressures are for 19's right?

 

Looks like I was running mine too hot them. I was well over 35 psi hot. Closer to 39 if I remember right.

Are you still running Pirelli's?

 

Yeah yeah yeah

 

Hmmm, System's on the car for this weekend, Trofeo's up to bat next, MPSC's in garage for cooler weather. I am tire rich and cash poor