S03 owners, what tire pressure do you stick with when driving alone?
10-26-2001, 11:29 PM
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What size tires you have?
I've got 225/40-18 and I run 38psi. I haven't done a whole lot of experimentation to see what works best. I think 36 is the minimum, but I worry that 40 would be too much when the tires got hot.
Zaid
Zaid
10-27-2001, 06:30 AM
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No, no, no! Higher cold pressures usually means lower hot pressures.
Less cold inflation=more flex. More flex=more heat. More heat=higher hot pressure.
On the track with PPS02s, I start 43.5 ft, 42 back. On the road 40/38 or 41/39.
RR
On the track with PPS02s, I start 43.5 ft, 42 back. On the road 40/38 or 41/39.
RR
10-27-2001, 09:30 AM
#5
That's correct. Higher speed requires higher pressures for the heat transfer and reduced flex...
Flexing sidewalls create heat and that is what causes tire failure. More air pressure improves the heat transfer of the tires. Tires generate higher temps when running at high speeds due to friction in general in addition to sidewall flex.
Too high pressure causes excessive wear in center tread ribs, and can possibly result in "bruising of the belts". General rule of thumb is that more problems come from too low inflation vs. high - or that more people are driving around with underinflated tires.
If tires can handle the pressure cold, it will be OK at operating temps - always higher at operating temp; that's why you need to check them COLD.
Too high pressure causes excessive wear in center tread ribs, and can possibly result in "bruising of the belts". General rule of thumb is that more problems come from too low inflation vs. high - or that more people are driving around with underinflated tires.
If tires can handle the pressure cold, it will be OK at operating temps - always higher at operating temp; that's why you need to check them COLD.
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