[Old Henry]

How much does your car weigh? Optimal tire pressure depends on the weight of the vehicle. Too much and you wear out the center of the tread. Too little and you wear out the edges. My operator's manual says 28 psi for my 3,420 lb 47 fordor with stock 600-16 bias ply tires. That's what I've run for 71,000 miles through three sets of Coker B.F. Goodrich Silvertowns. They have always worn evenly across the tread and ride much smoother than higher pressures that I've tried temporarily. So, unless your car weighs more than mine (wouldn't think for an older chopped coupe), you shouldn't run any higher pressure in the 600-16 bias ply tires than 28 psi. You'll wear them out early in the middle of the tread. I would think more along the lines of the 26 psi that CT AV8 recommended. Larger rear tires on the lighter end of the car probably even less pressure than that.