Looking for opinions on a starting point, I have 8psi stuck in my head but may be way off base

Hoosier 33x17x16 c07
Pro stock truck about 2500lbs with driver 950ish HP, 456 gear

I run a smaller Hoosier tire (18370) 33.0/15-15 D05 on 15 inch rims from 6.5# to 7.5# depending on the track surface. This with a 1.80/4.29 gear set at 2150# (with driver) seems to be the pressure that produces the best results. If I'm at a really well prep'd track I could probably get away with 8 or 9, maybe a bit higher.

Bob

start at 7 and move up or down .2 to see. i am at 2290 with 1200hp and run generally 6.8