<VV> tire pressure

[Michael Kovacs]

  I'll be at the track in NY this weekend. When I ran at the Thunderbolt track and a few others, it seems like my Corvair (1966 4 dr 140 PG) pushes/under steers/tight in the corners using stock suspension, all season street tires 185-70-13. I was running 30 psi in the front and 40 psi in the rear. 
 I don't want to make any changes to the car suspension as it is my everyday driver using 20 psi in the front 32 psi in the rear
 Any suggestions for track pressure?