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Tire pressures

> I use 40 psi only when autocrossing, giving me stiffer sidewalls so it 
> wont bead off the rim, because autocrossing is relatively low speeds.  I 
> made the mistake of driving home from an autocross with 40 psi tires, and 
> it was awfull. The high speed stability was not there, at 110, I had to 
> fight to keep it on the road, when normally I could have my feet up with 
> a beer.  That high of pressure will also wear your tires wrong, wearing 
> the middles quick and not touching the outsides.  I run 35 front and 32 
> rear, which is a good street balance.  (BTW, same size tires as yours...)

I have an experience ( and questions! ) relating to tire pressure. I have 
some tires, that are not very highly rated ( $100 or so ) with a 60,000 
miles warentee ( read " not sticky rubber - family style M+S tires " ) 
and I was up the canyon driving the other night. I drive FAST through 
those curves, and I could feel my tires loosing grip around most of the 
turns. When this happened, it was a sort of skidding grab-jump-grab-jump 
kind of traction. It was sort of disconcerting at first, but I got used 
to it. I was wondering : Do all tires lose traction like this? I thought 
tires would actually skid, not bounce-skid...? I drove the same tires 
through a yellow light/left hand turn about 40-50 mph on cement, and they 
slid (did I mention that they squeeled? they did. ) the way I would expect 
tires to skid. I feel that it is because of the cement, and that for 
whatever reason, it doesn't have as much friction as asphalt (Sp?).  Am I 
after this little mountain escapade, I looked at my tires in the morning. 
They all had little bruise/scrape/burn marks around the first couple or 
three inches of the sidewall. Was I actually folding the sidewall over? 
I was running street/dirt road pressures of 35 psi. Usially if I go 
'mountain racing' I jack them up to 40-45. Would this have helped me? 
Should I just go spend the cash and get some good Z rated tires with 
stiff sidewalls? Or should I keep trying to play the 'beat the 60,000 
mile warentee so I can get new tires for free game'?

thanks ( for reading this book^H^H^H^H long message )

bo            bellis@ensr.com               Brooks Ellis                  de
rn          You know how we do it       brooks@alpha.pr1.k12.co.us        si