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Old 12-23-2009, 09:05 PM   #93 (permalink)
dremd
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[QUOTE=winkosmosis;149709]In order for this experiment to be valid, you'd have to apply downforce equivalent to what a real tire experiences, and you can only measure static friction.

The force of gravity pulling the block down represents the force of the car.
Are you implying that the experiment needs suspension?

Quote:
Originally Posted by winkosmosis View Post
In other words, you might as well use a real car. And real cars prove that higher pressure inflation pressure = smaller contact patch = less total traction.
How exactly do you claim that?

Quote:
Originally Posted by winkosmosis View Post
Or just try telling an race driver that tire pressure doesn't affect grip because your blocks and scales said so.
The primary Reason why the lower pressure is used in race cars is heat (see linked Article in post #1).

I'm not totally naive about tires at the track.
My Racing Credentials are totally amature.
77 SCCA SOLO II "trophies", a hand full of best PAX scores, and one fastest time mostly in an 89 N/A Auto Supra With Tires in the 55 psi zone (Had no Idea why at the time, other than Butt Dyno and times) (depended on temp) or about 30 in the Wet (Boy Did I love embarrassing EVO's and WRX's in the rain).
4 "stunt driving" Credits in Commercials All local . . . .
A hand Full (10?)of Track days in various Supras
2 Track Days in the Golf tdi
1 Track Day in the Lemons Car
2 Lemons Races.
Went Drag racing basically every weekend for 4 years (told me to quit coming back to bracket racing), mostly in a slow 87 Turbo 5 speed supra.

(Good Lord have a wasted TONS of Gasoline)

I do not Claim that in racing conditions that higher pressures don't affect anything, what I claim is that on the street (DRY!) higher pressure has no/ very small affect on stopping distance.

Edit: I'm 99% sure that this has already been posted in this thread, but http://www.nhtsa.dot.gov/cars/rules/...ure/LTPW3.html
Why would data provided by good year look like higher pressures decrease stopping distance, granted chart stops at 35 PSI.
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