iagree I'd start around 18 psi. If the car hooks good, you can add some pressure until it doesn't. Since you only get one time shot before the race, try it at 18..if it hooks, leave it alone. twocents

CHIP
'70 hemicuda, 575" Hemi, 727, Dana 60
'69 road runner, 440-6, 4 speed, Dana 60
'71 Demon 340, no drivetrain, on blocks behind the barn
'73 Chrysler New Yorker, 440, 727, 8.75
'90 Chevy 454SS Silverado, 476" BBC, TH400, 14 bolt
'06 GMC 2500HD LBZ Duramax