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Lightsped said:
I have heard quite a few people say that it is best to put more air pressure in the front tires as compared to the rear tires. According to many people, this reduces understeer.

IMHO, it would seem more logical to put more air pressure in the rear tires to "round" the tires footprint out more, which would reduce grip, which would increase understeer.

Seems like "rounding" the front tires footprint out, would reduce grip, which would create MORE understeer.

Please, someone clear this up for me.
To a point increasing pressure in the front vs rear will help to reduce understeer. Every tire will have an optimum pressure producing the most grip . These are the pressures you should run, anything less or more your compromising grip. As schischwein pointed out there are better ways to deal w/ under/oversteer- sway bars, camber adj, springs etc. The only people really forced to use tire pressure in addressing handling characteristics are those in stock autox classes- they are limited in what suspension mods can be done.
 

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That might be a smidge high, that's real close to what I run in autox, street I'm running 36f/33r- that's w/ a very stiffwalled T1S though.

If your ride is not uncomfortable at those pressures, then I'd stick with them as your well below the maximum pressures for that tire. If your ride leaves a little to be desired comfort wise you could probably come down a couple of pounds f/r- don't let it become squirmy however as you mentioned.

The only way to find the "ultimate" tire pressure (most adhesion) is w/ a 200' skid pad (or track) and a pyrometer. Essentially taking three measurement across the face of the tread of each tire and adjusting pressures from there. It's aslo a good way to see if camber adjustments are where they need to be. Someday I will actually do that- pyrometers aren't really that expensive.

For autox, I look at roll over on the tread (some use white shoe polish for this)- essentially if the tread is scrubbed to far onto the sidewall - I adjust pressure up, not far enough onto the sidewall- pressure down. Not the most scientific, but until I get a pyrometer it will have to do.

Big Sky
 

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There are some good infared pyrometers out there, they run in the ~$150ish range. They're pretty accurate and fast. Most normal pyrometers also run in the $150ish range, with some in the $300-400 range that store 10 seperate (12 temp each/3 per tire) runs and dispaly all 12 temps at once- probably a little over kill (at least for me).

The nice thing about an IR (if has a adequate range) can measure other components as well (the regular pyrometers can also w/ different probes).
 
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