What is recomended?
Temp is about 60 outside..
Temp is about 60 outside..
Recomended tyre pressure at the track.
- Thread starter BITeR
- Start date
With stock tires, I've found that the factory recommended 33 psi front and 40 psi rear work fine.
With track tires (Yokohama A032R), I use somewhat lower pressures - I forget exactly how much, but in the low thirties (maybe 31F/35R?). I know some people who even use pressures in the high twenties with the A032R.
With track tires (Yokohama A032R), I use somewhat lower pressures - I forget exactly how much, but in the low thirties (maybe 31F/35R?). I know some people who even use pressures in the high twenties with the A032R.
Ok, I need a refresher on tire pressure theory.
You optimum tire pressure is the lowest pressure possible that does not allow the tire to "roll over" on the sidewall, correct?
Lower pressures mean better traction, right?....of course, unless you're twisting your sidewall into a preztel.
What am I looking for in an optimum track pressure? Autocrossers jack the pressure up high to prevent the "rolling", drag racers drop it for stick. Am I correct in believe I am looking for that balance point between the two?
Bill
You optimum tire pressure is the lowest pressure possible that does not allow the tire to "roll over" on the sidewall, correct?
Lower pressures mean better traction, right?....of course, unless you're twisting your sidewall into a preztel.
What am I looking for in an optimum track pressure? Autocrossers jack the pressure up high to prevent the "rolling", drag racers drop it for stick. Am I correct in believe I am looking for that balance point between the two?
Bill
In general optimum tire pressure for a given tire is one in which there is even tire temp across width,assuming the tire is making full contact with the pavement(higher temp inside when neg camber is used).Hard working track tires or street tires used at the track should have thier target hot temp at around what is suggested by the manufact or on this site.The problems for the novice arrise because they don't realize that you must allow for tires to increase thier pressure 6-10 psi on a warm track.So if target hot is 38 you might have to start with 30-32 cold.
docjohn said:
Oh yeah, they're stock 91's with S-02 PP.
So stock pressure is ok then?
The reason why is because they heat up a lot?
If I only do a few laps at the time (it's a driver training event) I should increase a few pounds?
thanks
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')A lot depends on how hard you're driving in these events. The harder you wail on your tires, the more air you need to bleed.
What I've done in the past at DE events (this is on a 92 Mustang) is start at about 28 psi for the first session, and then check the pressure shortly before the next session, and bleed off air if the pressure is above 30 psi. After multiple sessions, your tires will obviously be hotter than at the beginning of the day.
If you have a tire temperature gauge (I didn't, but I was able to borrow one), that goes a long way to figuring out what the correct pressure should be.
Another way I was shown was with a piece of chalk. Your tires should have a mark all the way around on the sidewall, relatively close to the tread, that shows how far the tire can roll over. Make marks in 3 or 4 places on your tires, going from the side of the tread towards the center of the wheel, just past the mark.
When you come back from a session, check how far the chalk marks have been scrubbed off. If you're close to the roll over mark, your pressure is good, if it's barely gone, it means your pressure is too high, and if the chalk is gone past the roll over mark, you need to add pressure.
Also, tracks in general will have more left than right turns (or vice versa), so your pressures willl vary from side to side on your car, since the outside tires will heat up more.
Hope that all made sense, and applies to NSXs.
George
What I've done in the past at DE events (this is on a 92 Mustang) is start at about 28 psi for the first session, and then check the pressure shortly before the next session, and bleed off air if the pressure is above 30 psi. After multiple sessions, your tires will obviously be hotter than at the beginning of the day.
If you have a tire temperature gauge (I didn't, but I was able to borrow one), that goes a long way to figuring out what the correct pressure should be.
Another way I was shown was with a piece of chalk. Your tires should have a mark all the way around on the sidewall, relatively close to the tread, that shows how far the tire can roll over. Make marks in 3 or 4 places on your tires, going from the side of the tread towards the center of the wheel, just past the mark.
When you come back from a session, check how far the chalk marks have been scrubbed off. If you're close to the roll over mark, your pressure is good, if it's barely gone, it means your pressure is too high, and if the chalk is gone past the roll over mark, you need to add pressure.
Also, tracks in general will have more left than right turns (or vice versa), so your pressures willl vary from side to side on your car, since the outside tires will heat up more.
Hope that all made sense, and applies to NSXs.
George
I would start with the recommended pressures of 33F/40R, measured cold, and adjust from there as necessary, in two-pound increments.BITeR said:
As docjohn notes, the optimal tire pressures will result in a uniform temperature gradient across the width of the tread. (Too high and the center will be hotter than the edges; too low and the edges will be higher than the center.) At the track, you can check this with a pyrometer (a device for measuring surface temperatures) to determine where you need to make adjustments.
