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Question w/increase in tire psi after driving

12 May 2000
Redmond, WA
I noticed that after driving, the psi on my tires are consistently about 1.5 - 2psi higher. After spirited driving, I've measured as high as 3.5psi higher. Now, factory recommendation on NSX tires are 33/40 and that the measurement be taken when tires are cold. Which means that during driving(after tires have warmed up), you're going to be running higher psi than recommended.

So, the question is:
Isn't driving at higher psi than recommended going to cause uneven wear? Or even increase in possibility of a blowout because you're running higher psi?
No. And no.

The air pressure increases as the tires warm up. But your cold pressure doesn't change. IOW Acura recommends that the tires be inflated to 33F, 40R cold pressure, which is when they should be measured. If you then go for an aggressive drive and they heat up to, say, 38F, 45R, they are STILL inflated to 33F, 40R cold pressure. IOW Acura's recommendation is that they start out (when measured cold) at 33F, 40R even though they will gain pressure when they warm up. When they cool down, they should again measure 33F, 40R.

Just to elaborate further: At the track, cold pressure is still your basis for measurement. Let's use the same example, and let's say (for whatever reason - handling preference, etc) you decide you want more pressure in the front, and the hot pressure is 38F, 45R when you measure it at the air pump. So you might add two pounds to the front tires making them 40 psi. Then, your cold pressure would be 35F, 40R because you added two pounds in front to the tires after they were originally 33F, 40R.