Tire pressure

[Bicyclops]

I'm running 215/35R18 and 255/35R18 Pilot Sport 4s. I've been using 33psi and wondering if I'm in the ballpark. The sidewalls are so short that I'm afraid of banging the rims in potholes. The ride is on the rough side. My buddy's Cobra with lots of sidewall rides like a Caddy compared. They don't seem to lose much pressure. Every time I check, they're about right where I left them.

So anyway, a couple of days ago my car started pulling hard left under acceleration and darting right when I'd lift. I cut the drive short and got in my truck to do what I needed to do that day. Last time it did something like that I found the Jesus bolt and one of the lateral arms loose. The left rear was changing toe under accel. Scary. This time I found a screw in the left rear tire. It felt like the other time only a lot more so. Got that fixed and she drives right again. It's been a long time since I had a low tire and I don't remember that kind of behavior.

Ed

It's been mighty quiet here lately.

[Shamilton289]

I’ve heard 10 psi per 1,000 lbs.
so 22-24 may be more appropriate
You can check YouTube for Tire Pressure Chalk Test

[GoDadGo]

I run 25 PSA because my car tips the scales at 2,535 wet.
By the way, what car do you have these tires on?
Those donuts seem rather small for a Cobra.
I'm running an oddball stagger on mine too.

https://youtu.be/iwslgKJUaKc

Good Luck & Happy Motoring!

[Bicyclops]

It's an 818S. I'm at about 2200 lbs. I did try the 10psi/100 and didn't like it, but I can't remember why. It does seem like I'm wearing to the sidewall markers.

For higher profile tires it is probably good. I'll try it again.

Ed

[Bicyclops]

Just looking around with a search engine, it seems that the low profile tires typically do want more pressure. That said, it's a pretty light car. I need to chalk them up and play with it.

Ed

[driveslikejehu]

I have 215/45-17 , 245/40-17 on my R at abt 2285# with me in it. I run 22psi cold, let em get up to ~25 at the track. Seems good.