tire pressure for racing twisties?

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Old Dec 2, 2003 | 04:00 PM
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tire pressure for racing twisties?

I'm just looking for a straight answer if i can get one. I like to drive really really fast on back road twisties just about everyday of my life and i was wondering what the proper tire pressure for both front and back for the WRX.
right now i just have iit at what the booklet says is good. but what do you think?

rich
Old Dec 2, 2003 | 04:04 PM
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i would keep adjusting until it's right. do what people do at autox, use shoe polish on the edge of your tires. if you are running hard with stock tires with manufacture suggested pressure, i say you are running too low. most likely you'll roll your sidewall. also, remember 10 degree outside them drop = 1 psi drop.
Old Dec 2, 2003 | 04:06 PM
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oh come on people. someone has to a least have a clue. I know Pete does.

And no these are not racing tires
they are just Y rated street tires on 17" wheels. They have a harder compound with a high tread wear. but still hold the road well.
Old Dec 2, 2003 | 04:08 PM
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Hey thanks for the answer
Old Dec 2, 2003 | 04:09 PM
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http://www.tirerack.com/tires/tirete...n/racepres.htm
Old Dec 2, 2003 | 04:11 PM
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I don't run the stocks anymore. man those sucked. but yes i've noticed the wear along the side walls of my tires is getting pretty bad from pitching the car sideways on wet roads etc... I'll look into increasing the pressure
Old Dec 2, 2003 | 04:12 PM
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I would start with 35 COLD all around and go from there. With the shoe polish, you'll be able to tell if you are under inflate (shoe polish disapprearing on sidewall) or over inflate (still have shoe polish left on the tire surface). After you get your max footprint. it's up to you how you like your car handle. See the link I provided for adjustment. of course driver input make a BIG difference as well...
Old Dec 2, 2003 | 04:15 PM
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thanks.
hey hows the car?
Old Dec 2, 2003 | 04:15 PM
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Yeah, Leo's suggestion is pretty much what I'd say too.

Starting from the "suggested" numbers, I'll usually bump them up a couple pounds beyond that and see how it feels- the shoepolish/chalk thing is a good way to see how much the sidewall is flexing, you don't want them rolling over very much if at all.

A lot of it it comes down to your personal preferences, different tires have different characteristics.
Adjusting pressure is about the only way you have of adjusting tire performance, but it really can do a lot to effect the handling.
Old Dec 2, 2003 | 04:16 PM
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oh, two things...

1. if you are only driving hard on that road. you might not want to use that set of tire pressure for regular driving. You might end up with too much pressure (smaller foot print) for regular driving.

2. if you are using those portable air pump. DO NOT trust the gauge on that thing. Use a real pressure gauge.
Old Dec 2, 2003 | 04:18 PM
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running good, thanks! But I am still on my SCARY RE92s

Originally posted by bushido
thanks.
hey hows the car?
Old Dec 2, 2003 | 04:22 PM
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Thanks guys. now i can't wait to start trying out the new ideas you've giving me. Show polish hhhmmm..... Maybe chauk would be easier???? I'll figure something out
Old Dec 2, 2003 | 05:00 PM
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it would help if you said what kind of tires you had, besides hard compound 17" street tires with a speed rating of y and high tred wear.

manufacturer and model with size
Old Dec 2, 2003 | 05:04 PM
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Originally posted by wrx ish
it would help if you said what kind of tires you had, besides hard compound 17" street tires with a speed rating of y and high tred wear.

manufacturer and model with size
yes it would, depending on the stiffness of the sidewall, the needed pressure will vary greatly.

example, with falken fk-451's (soft sidewall) or toyo t1-s's (extremely soft side wall) i would run anywhere from 38-50 psi.

on the s-03's that i have now im running 35 al lthe way around and its almost too much.

you can try various things such as biasing higher pressure to the rear and so on, but try to find a good base pressure for your tires first, that way when you do start letting air out of 2 of them, you know what those 2 tires will be doing.
Old Dec 2, 2003 | 06:27 PM
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With the RE-92s, I ran the max rated pressure in the front and 3lbs less in the back.



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