991.2 track tire pressures
 

Does anyone have some tried and proven ultimate hot race track tire pressure settings for 991.2 running 20" Pirelli P Zeros? I have been running my 2017 cab on Area 27 and have experienced pressure increase up to 15 psi, to over 50, which surprises me.

Depends on the track, driver and alignment settings.

Rule of thumb is with a advanced driver a tire will heat up around 8-10 psi. Seems most tires run best hot from around 30-34 front and 32-36 rear...again depends on the tire, driver, track and alignment settings.

Thanks for that mdrums. To clarify please: do you mean the pressures you quoted are the STARTING pressures when cold, or the ultimate pressures after they have risen 8-10 psi?

Ultimate hot pressure. Starting pressure will depend on outside air temperature and hot fast hard you drive and heat tires up.

Start with around 28psi/...you can't go to low otherwise they could damage. If you go lower on first session you'll need to do a few slower laps until they are warm. The first session you can live with the high tire pressures that will most likely result (close to 40psi) or just stop after 5 or so laps and adjust. Either way adjust them right after your first session when still hot to around 32-34 PSI and you should be good the next few sessions. Always check and correct PSI after each session though. I always start my MPSC2's at 26PSI but I had TPMS on to let me know when they were warm.

@Turtles, I followed you advice with good results. Thanks again.

Glad it helped, keep adjusting to what works best for you. Everyone drives a little different, has a different set up, car, etc, so what works best for you might be a slightly different.

Mark