I am planning on run a true street class this weekend. Car must be licensed and inspected, DOT tires and drive a 15-30 mile cruise with check points.

I have a set of ET Street Radial 325/50/15, but I have not ran them at the track for a few years. I bracket race with ET Drags and the car has been running 6.80s with 1.49 60' time. Car is around 3650 with driver, Calvert 90/10 shocks on front, Stange double adjustable on rear and Caltrac bars and springs.

I probably will only get one pass before my qualifying, so i am looking for a starting point for the tire pressure. Should i change the rear shock settings?

18-20 psi

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.

I run 255/60's @ 19 psi. Used to run them 18 psi, but when I bumped them up a lb, I found my 60's were a little quicker.

19 psi here caltracs, double adj all around 1.41 60 ft.

If you have them on a 8 inch rim try 18 lbs, if on a 10 inch or wider rim try 20lbs Not all gauges read the same pressures on the same tire by the same person I have more than one tire gauge, two cheap Moroso 0 to15 lbs, a digital bycycle racing gauge and a real expensive low pressure (0 to 12 lbs in 16 of a lb increments) analog gauge. I now use one of them only, don't get your self confused by having multiple gauges Take the time to expermiment to find the best pressure for your car I ran M/T 325x6060x15 ET Street radials on both 12 inch and 10 inch wide rims, I ran them on my 3450 lb Duster, it like between 18 and 22 lbs them according to my notes on my gauge IHTHs

Thanks guys, that gives me somewere to start.

Adding pressure will make the car faster if you can keep em glued. From my experience w/ the radials, they will still hook really good down around 17 psi, but the track and your suspension better be good if you're gonna hook them w/ high pressure. That's why I said leave em alone at 18 psi if it hooked b/c you're only gonna get one time shot before eliminations. First round is not the time to try something new.