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Low Pressure in the V710s

Old Sep 6, 2006 | 02:01 PM
  #1  
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Potato Love
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From: Normal, Illinois
Low Pressure in the V710s

I've done a few SOLO events in my V710s, and it seems like I run really low pressure to combat understeer in very low speed turns. How low is dangerously low? The courses in my region tend to be tight and well suited for Miatas, with very few areas where I can use the FD's power. I'm typically in the 20's for pressure, while most guys are running theirs in the 30s (the 710s are popular in my region).
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Old Sep 6, 2006 | 02:09 PM
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The other guys are running their pressures too high

My car runs 225/50/16 V710 on stock wheels with 2 degrees of negative camber at all 4 corners.

For (high grip) concrete I run 28 front/26 rear. For (less grip) asphalt I run 26 front/25 rear. My pyro and course times say these pressures are good.

I agree that the 710 feels better to the driver with higher pressures (especially the steering), but grip is less. The car feels better, but it goes slower.
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Old Sep 6, 2006 | 02:54 PM
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Potato Love
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From: Normal, Illinois
Originally Posted by DamonB
The other guys are running their pressures too high

My car runs 225/50/16 V710 on stock wheels with 2 degrees of negative camber at all 4 corners.

For (high grip) concrete I run 28 front/26 rear. For (less grip) asphalt I run 26 front/25 rear. My pyro and course times say these pressures are good.

I agree that the 710 feels better to the driver with higher pressures (especially the steering), but grip is less. The car feels better, but it goes slower.
****. My pressures are almost exactly the same give or take a pound. I still haven't done any camber changes. I'm doing suspension work this winter since I run ASP, anyway, so I'll re align the car then.
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Old Sep 6, 2006 | 09:06 PM
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I run 215/50/13 710s on my FB with 2 degrees on negative camber, 29 in the front and 25 in the rear. I have played with it and this is what seems to work.
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Old Sep 7, 2006 | 12:27 AM
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I'd actually start high and work my way down. and adjust the pressure based on how the car is handling and also the type of track it is. If it is a tighter course, we tend to run higher pressure in the back, etc.
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Old Sep 7, 2006 | 12:57 PM
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V710 like lower pressure to get temps up. Kumho engineer Frank Secondary recommends hitting 210-220F but not over 240F....I can never get anywhere near that range. The old Victoracers liked higher pressures so when I first got V710s, I ran 38psi like before. It was not gripping at all...I then dropped it by 10psi to 28psi and shaved 1 sec off overall.

The V710s seem to like more slip angle (kinda like Hoosiers) so you need to preturn but steady state grip is excellent. Although I do prefer the quicker transient response of the Victoracers.
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Old Sep 7, 2006 | 08:39 PM
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From: Normal, Illinois
I never hit those temps, either. A viper guy bummed me his tire thermometer. I don't think auto x puts them through enough to get up that high.
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