I'm running the same tires, but with a lower stall (3500) and higher gears (4.10) in my '74 Duster. For me, the tires hook best at 19-21 PSI. Rear suspension is SS springs with Mopar Performance drag shocks. Before I got the rear suspension geometry set up right, I spun pretty bad. Now, as long as track prep is right, I get no spin.