taffin

Hi,

I have a track day today in 33deg Celsius at Yas Marina.

What should cold starting and then hot pressures be?

Running a 2008 gt3
235 35 19
305 30 19
Pilot sport

Thanks in advance

BBMGT3

I was advised 33-34 psi HOT (like, really hot) all around.

PS2 or PSC? I am on PS2

CRex

On MPSCs, I start with 27F/28R and shoot for 32F/33R hot. However it starts getting greasy in the back real quick once I pass 33. If I'm not at my best I'll bleed it down to 31--buys me more stability even if that costs a bit of extra tire wear.

tcsracing1

22 all the way around cold

FFaust

Ballsy!

sin911

It all depends on how hard you drive and how hot the weather is. In FL summer the tires build up 10 psi no problem...

kyrocks

I start with 25 psi COLD. On hot days, I may need to take a couple psi out. My goal is 32-34 hot. I also look at the tire sidewall to make sure I'm wearing to the edge of the tire, but not scrubbing the side. Pyrometer can help as well - can't easily change alignment/camber at the track, but if the middle of the tire is higher (more than 10-20 F) than the inside or outside of the tire, you are overinflated. Have fun - pressures are different for everyone due to different tracks, different climates, and different driving styles, but this should give you a starting point or rough idea. Good luck.

M3EvoBR

My tires build more than 10 psi in the back when in full thread. I usually use 32F and 34R. Works for me on RA-1

996FLT6

28 cold all around for street tires. It's a warmup session. Easier to bleed down then add air in. Some tracks have no airtanks. Mike

tcsracing1

again, in 33 degree weather, 22 cold all the way around. 19" MPSC.

at temp fronts will hit 31 and rears will see 36

one question however: nitrogen or air?

taffin

so been going 26/28 cold, which builds up to 32/34 hot.

Can't start at 22, ambient temp is too high 24hrs a day so inner sir already quite warm.

I then deflate after running 20 min or so of the first hour.

In second session, I run 2-3 laps then check again.

Using air, not nitrogen. Although no air tanks at the track, at Porsche Club track days, Pirelli sent a truck out fully equipped with all tools.

mdrums

So on Michelin Sport Cups hot should be 32/34? This is a tad lower than I ran R888.

Do MPSC like more or less camber than R888?

I'm at -2.5 front and -2 rear and that is a tad to much negitive camber for the stiff R888.

taffin

I am running PS2.... cups in short supply here

mdrums

I use to track PS2 a while ago. Being a street tire they have a softer sidewall and need more pressure for support. I found hot pressures of 36 front and 38 rear worked ok.

a lot of this depends on your alignment specs, track and driving...but this will get you into the ball park with PS2

stujelly

So dumb question are you guys running regular air from a air compressor or are you using nitrogen from a tank.