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track tyre pressure

Old 08-31-09, 11:01 PM
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track tyre pressure

i got a fd that im going to race on the track soon,it has 235/35/19s on it and was wanting to know what tyre pressure to run them at,on the street i have 40psi,and have been told to have them at about 28/30psi for track use,the tyre/rims on it were on the car when i bought it and are near new so i will use these untill i need to get 4 race tyres,is 19inch to big for track,sealed hill climbs,the fd is at a good ride height with hks adjustable coilovers,feed swaybars,cheers...
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Old 09-06-09, 06:31 AM
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I would start at 30psi. You're at the same width as stock.

Not sure why you're running 40 on the street that seems a bit harsh.
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Old 09-06-09, 09:37 AM
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In my limited track/AutoX experience, I've found that 30psi is a good starting point as David said. ALWAYS check them after a session. The first session they will spike significantly going from completely cold to hot. After that, it's normally bleeding off a couple of psi's a session. Any 17 or 18in tire I have ran on the track(and I've tried several different sizes), I have ultimately ended up at ~28-29psi in the front and 26-27psi in the rear at any track I've ever driven on. Some of those being street tires, some of them being R Compounds.
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Old 09-06-09, 09:47 AM
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30 front 28 rear.. that's what i always run
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Old 09-09-09, 11:34 PM
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a tyre shop told me to run 40psi all round for the street,i thought that was a bit high but hes the tyre man not me,i will go back to 36psi for street,for track i will go with what you guys say,cheers.
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Old 09-11-09, 08:29 AM
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Question - are you guys talking about 28-30psi Cold or Hot?

When I used to track my FD on stock rims and tires, I found 31f/29r cold temps (car sitting at least an hour) to work pretty well, IIRC.

But that was a while ago, so I could be confused.

-b
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Old 09-11-09, 10:38 AM
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Originally Posted by wrankin View Post
Question - are you guys talking about 28-30psi Cold or Hot?

When I used to track my FD on stock rims and tires, I found 31f/29r cold temps (car sitting at least an hour) to work pretty well, IIRC.

But that was a while ago, so I could be confused.

-b

yeah big difference between cold and hot! you're talking about a 150-200 degree change in temprature, air expands
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Old 09-11-09, 05:02 PM
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I'm talking 28-30psi cold. Hot goes up about 5 psi for me and I usually leave it there.

With better tires you can easily run 28-30 hot but that's only after the proper methods are used to verify tread temps and stuff.
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Old 09-15-09, 04:08 PM
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We run an FC with 225/45-15 and we are around 30-32psi in front and 28-30psi in the rear.

I usually run 2psi difference from front to rear, and I leave more/less in the rear to balance the car for the day. Nothing too scientific.
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Old 09-15-09, 05:52 PM
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Originally Posted by wrcRS View Post
We run an FC with 225/45-15 and we are around 30-32psi in front and 28-30psi in the rear.
What tires and is that hot or cold?! I run 205/50r15 Toyo RA-1s on the track car and run 24-25 cold on all corners. I tried going to 28 the last time on track and it was twitchy to the point of being scary.

I'm going to 245/50r15s on the next set of tires and was planning on a max of a pound or two higher (since they should run a bit colder than the 205s).
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