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Re: Tire Pressure - P zeros Posted by Ari [Email]  (#2847) [Profile/Gallery]
(more from Ari) on Fri, 8 Apr 2005 06:26:22
In Reply to: Tire Pressure - P zeros, starship, Thu, 7 Apr 2005 20:02:27 Members do not see ads below this line. - Help Keep This Site Online - Signup |
From what I could dig up, the Pzero max pressure is 51 psi. That's the max pressure, not the recommended one. The shop did a very bad thing. That's like saying if the max speed of the car is 135 mph, you should drive there all the time.
Tire pressure depends on the tire, car, and your driving style. In general, the higher the tire pressure, the better the handling, but the stiffer the ride. Lower tire pressure gives a better ride, but reduced handling. Pzeros are pretty serious performance tires, so they're biased towards handling over ride to begin with.
Next, under inflated tires wear quickly, reduce gas mileage, and handle badly (as above). Over inflated tires wear quickly, and if way over-inflated, handle badly (less tire on the road).
Of course, if the car is lightly loaded, you can run lower pressures than if you drive with four passengers, or four passengers and luggage and a full roof rack. If you regularly go into on-ramps at twice the posted speed plus 10 mph - really agressively, you'll want a higher pressure than if you're doing more sedate driving.
I'd start with 34-36 psi, cold. There's an old racer's trick - take some chalk, and draw a line across the tread and up the sidewall an inch or so. If you don't want to mark up your pretty new tires, use colored chalk, like blue, which only shows if you get up close. Liquid shoe polish works, too. Then drive the car as you want it driven. Then get out and look at the marks. If you're scraping the chalk off the sidewalls, the tires are underinflated, and you're rolling them over. If you've still got chalk on the outer edges of the tread, you're over-inflated, and not using all the tread.
Keep an eye on the tread wear. If you see more wear in the center than on the edges, you're overinflated. More on the edges than center, underinflated. That kind of wear will take a few hundred, if not a few thousand miles to show up.
If the car isn't handling the as sharply as you want, add some more pressure.
posted by 192.249....
, Fri, 8 Apr 2005 06:26:22 <-- Viewing This Message, Fri, 8 Apr 2005 10:10:37, Fri, 8 Apr 2005 11:05:19
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