Autocross Tire pressure 195/50VR15?

piperpilotduane · 02-06-2002, 05:43 AM

OK guys, I bought the Kumho 195/50VR15's. What tire pressures do you run during Drivers Ed events. I'm headed to my first one on the 15 th and want to be prepaired. Thanks for your input.

MJHanna · 02-06-2002, 06:59 AM

On running DE (track events) I run 26 cold all way around on 205/50/15 Kumos

HMeeder · HMeeder's Garage

I normally run 32 rear and 28 front (cold).

Depending on track conditions you may want to adjust as you go. I leave my rears alone and start with 31-32 in the front. As the track warms up and you get a feel for how your car is responding, lowering the front pressure will increase understeer or 'push'.

The track configuration may also dictate what you do. Last time I went out I was having a hell of a problem pushing on one particular corner. I increased the front pressure just to deal with that corner. I could compensate for the oversteer everywhere else on the track with the throtle and finally figured that one corner out.

Truth is, every car is set up slightly differently (shocks, sway bars, tires, torsion bars, driver's style) and you're gonna end up having to start with someon'es recommendation and adjusting as you go. You will eventually get to where you need to suit yourself and your vehicle.

I have friend who, like Hanna, runs 27 cold at all 4 corners.

Tire pressure (and some use temperature to make their adjustments) is one of the sweet mysteries of performance driving.

Good luck!

John Rogers · 02-07-2002, 11:31 AM

If the tires are Victoracers, I'd recommend 26 psi as mentioned. If it is hot (+80 degF), maybe 24 or 25 and if cold (+40 degF) then 28 psi. This is what I use in our 205 V700s on our stock 914. Good luck.

MJHanna · 02-07-2002, 12:34 PM

Don't forget to chalk your sidewalls. Look at where the tires are rolling over. If you have a pyrometer all the better, if not then, thank goodness for shoe polish.

Otto · 02-07-2002, 05:01 PM

A pyrometer is the only way to tell what tire pressure to run. You measure the inside tread on the tire, then the middle and then the outside., or outside, middle, inside. When all of the temperatures are the same, you have the right pressure. An underinflated tire may read the same as an overinflated tire, that is why you chalk the side of the tire to tell how much rollover you have on the sidewall of the tire. Remember that when you change the ride height of your car, you also change the toe. You must reset the toe whenever you change the camber, or ride height. OTTO