This will be useful info for when I get my rs3's...

 

Very surprising at some of the answers.

On big tires on narrower rim. I would go high 30s hot
On wide rim. I would go low 30s.
This is for rs3 and street tires in general.

I would run 5psi lower for rcomp


But u should use pyrometer to determine optimal psi.

 

Interesting mix of recommendations.

When I ran 225/45/15 RS3's on 15x8 wheels I ran 30psi front 28psi rear. Based off of pyrometer readings. those are hot pressures.

your numbers may vary to make slight balance changes. I'm on 750/450 AFCOs w/ RB 1.125" (soft) and FM 5/8" (med) w/ a splitter and wing.

 

Thanks guys. That info has been helpful. I am running FCM with 450/325. I think 30-32 hot should work fine.

 

on your S2000......

We were running 31psi hot, in quan's NC, all of this last season.

start with a target of 31-32 psi

 

This. If you are squeezing the 225 RS3s onto 7" wheels they will need a lot more pressure to be optimal than if you mount them onto 9" wide wheels. I run them on 7.5" wheels and usually have them at 35psi all around, I have seen run well on 9" wheels as low as mid 20's.

 

In for updates since I am ordering these tires to put the powah to the ground

 

FWIW, I just picked up a brand new set of these on 9" 6ULs. Two weeks ago at PIR I ran ~34 psi hot, and the tires were wearing to maybe an 1/8" above the arrows on the shoulders. That would suggest that 31-32 psi hot, as others suggested, would get me right down to the tips of the arrows. I don't have a pyrometer or anything, so that's about the best data I can contribute...

 

I'm picking up my 225/45/15 RS3s and 15x9 Bronze 6ULs from Phils Tire Service in NY Saturday. First Porsche Club Autocross at Tobay for the season Sunday. I was running 29f/24r with my 225/50/14 Hoosier RS305s on 14x7s las season. I don't have a pyrometer. Any suggestions on an affordable probe style? I'll let yall know how it goes.

 

See you there man

 

Feel wise I prefer ~36 psi HOT front and rear. 32 hot starts to feel too squirmy for my tastes.

Lower may be better for lap times but the feel bothers me.

 

I just ran my first auto x on a set of 225/45/15 on 15x9 6ul. I chalked the tires a couple time at different pressures. Even at 30 psi cold there was ZERO shoulder wear. Even all the way down at 26psi cold and retarded sideways driving I only saw a light scrub maybe 1/8" down the sidewall.

 

at 30 cold what did they go up to when hot

 

At no point in the day was my hot temp even a full 2 psi over my cold.

 

Cool. Thanks man. I need to hurry up and get mine mounted. I really need to look into getting more power this season also lol

 

What class are you running in the SCCA and what engine mods are allowed?

 

I run STR as for power mods just NA stuff nothing crazy. Anything FI would be SSM. A turbo miata with slicks and a good driver is hard to beat to be honest. Most of the time you would be trying for FTD and at that point who cares what class your in haha

 

I can second this. I ran an autox this weekend and we ran my car in STR with the tires at about 30-31 hot, and we still weren't seeing wear past the tips of the arrows on the sidewall. The guy that co-drove my car is very fast, and he was pushing it pretty hard.

 

I've done a ton of pyrometer testing the last two events and get the most even temps at 36 front, 31 rear, cold.

 

I had no idea you were testing like that you should of let me be part of the test group haha. I am still running 32 hot all around and the car seems fine. At the PSI your running are you using all the tire meaning is it using the sidewall at all. I been using those little arrows on the side of the tire. I like to see wear on that arrow if I don't i feel the PSI is too high. Well let me know what you thing. Also what is your alignment settings