What should tire pressure be at to prevent flat spots?

I think flat spots went away with bias ply?

I'll let you know in March when the vert comes out of hibernation. I took the tires off last year and stored it up on blocks. Won't make that mistake again! The blocks froze to the ground, and I spent about an hour with a blow torch and a sledge hammer getting them free so I could drive the car into the garage.

This winter, it's sitting on the nearly new Nittos.

By my own example, I wouldn't worry about it. If you do get flat spots, they'll certainly go away quickly once you start driving it again.

My car sat for ~ 1.5 yrs and didnt have any loss of air pressure or flat spots. Nitto 315's in the rear and and 275/40 Falken 615's up front.

my car sits for 6-8 months at a time without problems.. tires go smooth after a mile or so...

Old bias-ply tires were prone to flat-spotting, not modern radials. (parked for a reasonable period, I'm sure twenty years without moving might do bad things)

my car sat 5 years on flat tires and I still dont have flat spots! dryrot? yes, but no flat spots

Any tire utilizing nylon belts can or will form flat spots after sitting for long periods of time. Especially in colder weather. Bias construction OR radial. Many of the H rated and all of the Z rated "W" suffix & "Y" suffix radials today use 1 or even 2 nylon cap belts to keep tire composure or "growing" under control at real high speeds. Tire construction info is usually found on the tire sidewall in small print.

GT