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Discussion Starter · #1 ·
i'm sure this has been covered numerous times, and i did find a little, but i guess my search skills are lacking. sorry.

so the recommended pressures are 36psi in the front and 30 in the rear. i've seen a few posts on here when i tried searching that recommended 40 front, 36 rear.

so my question really is how the air pressure affects handling, mileage, and tire wear. both higher vs lower pressure and the effect of the difference between the front and rear pressure. for 1, why are the recommended pressures not the same for the front and back? is it a weight distribution thing?

as i understand it, higher pressure = better mileage, but mileage is not really my concern, if it was i would be driving a different car. :lol:

i want my car to handle as good as possible without wearing out my tires at an abnormally fast rate. i would like to reduce the understeer a little bit. i'm not so concerned about ride quality either, b/c again, i'd be driving a different car. :lol:

so what pressures should i be running.

extra info:
it's my daily driver
Fuzion HRis on it right now
stock suspension
 

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higher pressures will provide you better gas mileage (i tried this and i got 15 miles more a tank). Your tires wear more in the middle rather than on the sides. Handling is crappy also. I swtiched back to factory options. I would love to have better handling rather than saving 15 miles on a tank.
 

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I tend to run ~38 psi front and ~35 psi rear for the street and autocross. At the track I tune my hot pressures to 38 psi when I'm on street tires.

Tire pressures is a pretty personal thing and it's used for very fine tuning of your car's handling characteristics. On street tires the general approach is to add a bit of air to the end of the car that you want more grip, or drop some pressure from the end of the car you want to loosen up. Example... if the car is understeering bad, drop the rear by a couple of psi and it should help.

At the track I've found that when my STi's suspension was stock I got the best handling out of the car when the pressures were even when hot.
 

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You asked why more pressure in the front..well because the engine is in the front..the front tires have to support a good amount more than the rear..thus needing more pressure to sustain equality..that's the best way I can put it..
 

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Discussion Starter · #8 ·
thank you all for the replies. i suppose i will just have to play around with the pressures some and see what i like.

as for the tires, i want new ones (probably Kuhmo Ecsta MX, maybe Potenza RE050A Pole Position), but when i bought the car these are the tires it came with and they're almost new. hard for me to drop money on new tires when these have tons of tread left. maybe with my tax return next year! :D
 

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jomotopia said:
...i suppose i will just have to play around with the pressures some and see what i like...
Exactly. Since no one else has chipped in that is running those specific tires, it's really tough to give you any concrete advice. All tires like slightly different pressures with different set-ups and different driving styles - there is no "one psi" fits all.
 

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jomotopia said:
thank you all for the replies. i suppose i will just have to play around with the pressures some and see what i like.

as for the tires, i want new ones (probably Kuhmo Ecsta MX, maybe Potenza RE050A Pole Position), but when i bought the car these are the tires it came with and they're almost new. hard for me to drop money on new tires when these have tons of tread left. maybe with my tax return next year! :D
Change your W4. Who want's to give the government an interest free loan.

Back on topic: The OEM tyres suck in the snow. Puting a set of the 070's on in the spring might be very enlightening. Harsh ride, but vey good handeling. I run 42/36 psi.
 

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personal preferance. to a point. low rear kinda gives over steer. overly high is the same but more violent. low front is vague mushy better bump absorption. to high is twitchy rough and hop steer/slide. and your driving style will favor a set of pressures. stock is a compromise you may not like.
 
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