Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP
Posting-Version: version B 2.10.2 9/18/84; site watdaisy.UUCP
Path: utzoo!watmath!watnot!watdaisy!gvcormack
From: gvcormack@watdaisy.UUCP (Gordon V. Cormack)
Newsgroups: net.auto
Subject: Re: tire inflation pressures
Message-ID: <7354@watdaisy.UUCP>
Date: Sat, 20-Jul-85 11:17:11 EDT
Article-I.D.: watdaisy.7354
Posted: Sat Jul 20 11:17:11 1985
Date-Received: Mon, 22-Jul-85 05:26:48 EDT
References: <572@hlwpc.UUCP> <522@isrnix.UUCP> <161@husky.uucp>
Organization: U of Waterloo, Ontario
Lines: 24

> I'm no expert at automotive technique but I recall talking to some
> tire and wheel engineers who say that inflating tires over the recommended
> inflation gives better dry traction and better gas mileage but worse
> wet traction, and less smooth ride.  It also makes the tire heat up faster
> so decreases tire life.

There are two popular misconceptions here.  First, HARDER tires work
better on wet pavement.  The force per square inch between the tire
and the pavement is almost exactly equal to the pressure in the tire.
It is obvious that the higher pressure is better in overcoming the
lubrication film strength of the water.

Second, hard tires run cooler than soft, as there is less flexing of
the sidewall and tread.  It has been mentioned earlier, but the only
time that increased pressure hurts tire life is with unbelted tires,
where the centre of the tread may wear more quickly.

The last (and only) set of steel radials that I wore out were on a
'76 Mazda 808.  I kept them at 32 psi and got 85,000 miles out of them.
I regularly drove at 80+ miles/hour.

-- 
Gordon V. Cormack      CS Department, University of Waterloo
   gvcormack@watdaisy.uucp     gvcormack%watdaisy@waterloo.csnet