Auric

- PS4 Rear Tire with ~ 3 DE days on them.
- I've never noticed this type of tire wear in the past.
- No evidence of cording.
- I'm guessing due to overheating
- I was planning on running

them one more day/weekend.
- What do you guys think?

CosmosMpower

I can't comment on the chunks but it looks like you're running too high pressures as the center of the tire is wearing out much faster than the edges. I haven't used PS4S before but I wouldn't expect that much wear in 3 HPDE days unless you're doing very long sessions or 6+ sessions a day.

gbuff

Just from that shot it looks like more wear in the center than the edge=possible overinflation.....if it passes tech and if it's not raining I'd use it and keep an eye on it while also paying attention what the car feels like. Don't want to lose the rear on a fast sweeper......

Kitc2246

What car? Ran PS4S for four years. Agree, wearing in the middle indicating way too high tire pressure. 36 was my target with a Boxster. A 911 would be higher for the rear. How old are the tires, total track days/heat cycles? When was the last alignment? Typically the right rear will wear the most on the inside, the left less but also on the inside.

If you pass the track tech you probably could drive them, but I would not. They definitely won't pass a state inspection to drive on the street.

I would get a a season (4-5 weekends) and a half out of a set of PS4S. The left front edge would go first even with adjustable LCAs and more negative camber.

Bought mine from Tire Rack and COSTCO. Always got a track alignment.

Auric

- That's what I'm thinking
- I'll try to get one more day out of them

Auric

- One session later. - tires had 🐝 n flipped inside out - ps4, not seen this kind of failure in 200tw tires

ExMB

A PS4 is a 320 tire not a 200 tire. You ran too high of a pressure.

jdistefa

Those are cold tears.

The overinflation is making the central contact patch pressure excessive. You then heat up the outer layer (1mm) of rubber while the rest of the tire carcass is still relatively cool. The thin hot outer layer of rubber then delaminates from the cool thicker inner layer.

Auric

-thanks for the insight
- tires were 36 psi hot and 24-26 cold
- not sure how much lower I could go.

jdistefa

^ you have to start at 24-26 cold and then bleed in stages

remember to re-inflate your tires to some degree at end of track day

lower starting pressures risk damaging the sidewalls

other option is you can switch to nitrogen

badabing

Don't run those tires. They are beyond done.