So many variables... and the final PSI can change with different vehicles, tires/wheels (different tires of same size can run different psi), daytime temperatures, weather conditions ... the main decision is per event... street, highway, pylon autocross, hi-speed lapping (HSAX/HPDE). For performance driving (AX.HSAX, etc)... always increase a little vs daily driving. Where the heavier weight is (front engine)... run 2-4-6 psi higher than rear. Example street/hwy... front 34, rear 32..... AX/HSAX front 40, rear 36.. (some cars/tires etc... f 45, r 40, etc). You can also dial in understeer/oversteer/nuetrality.. experience and multiple events will tell you that.l

Look at TIRE RACK web site as they offer some recommendations.

For competition events, the chalk or shoe polish is a good practice, as well as temp measurements.

NOTE: www.mcscc.org MIDWESTERN COUNCIL OF SPORTS CAR CLUBS will have 5 season HSAX events this year 2019... Blackhawk Farms Raceway (HSAX School April April 27, HSAX race #1 May 27, HSAX race #2 July 5, HSAX race #3 July 6 (that's my club's race weekend!.. www.nsscc.org hope to see you there!). Joliet Autobahn HSAX race #4 July 20. BHF HSAX race #5 August 24. All these events are on www.motorsportreg.com for pre-registration (cost savings to pre-reg!). Also, all these events are HPDE (lapping sessions) morning and competition HSAX afternoon.

Last edited by Mopar Mitch; 04/12/19 12:02 PM.
Mopar Mitch "Road racers and autocrossers go in deeper and come out harder!"... and rain never stops us from having fun with our cars... in fact, it makes us better drivers! Check out MOPAR ACTION MAGAZINE, August 2006 issue for feature article and specs on my autocross T/A!