What pressure should I be aiming for when my tires are heated and up to race pace? Having trouble finding that spot that feels right
.I usually use 28 to 29,5 psi with my tunes.
I normally aim for just under 33.0 psi when hot, which is more often than not a starting pressure of 28.5.
I have a couple bullet cars that I am at a lower pressure. 26-27 cold. Other than that I am where PJTierney is at
I usually end up at around 33.5 psi when hot. Yet, if car feels great, the range of 32.5 to 34 is fine. Depending on the car and camber/caster settings it would require cold temps with about 28.5 to 30 psi.
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Thanks for all the good pointers… have settled in at 33 psi (2.27 bar for me) and that seems to be working just nice. Now I’m gonna see if I can become better and learn this tuning thing 
honest to god i do not believe adjusting tire pressure is meaningful in forza and i think craviator and takumi will agree with me. none of us ever bother changing it. 30 and 30 work on every car. i think tuning time is better spent on roll bars, springs and differential.
Hmm. I know that I’ve changed air pressure and saw no difference in handling before. Alot actually. But, I’ve made air pressure adjustments and saw improvment. Particulary with quietting down the tire “chatter”. I think since there’s no definitive method of tuning (example: stiff springs work for you, me not so much,etc.) that sometimes it helps and sometimes it dont. I’ve adjusted caster from 2 to 7 and didnt see any real difference in some cars, others you do see it.
28/28
Set it and forget it. I only alter if it’s plainly obvious that there is a skittish feeling. There doesn’t seem to be any real benefit in spending a lot of time on pressures though. I’ve tried messing with them after the car is tuned in order to hit the desired psi when hot and Tire temp and didn’t notice any change in the car’s reaction.