Phil wrote:
> Hmm. I ran SP8000s on the old Civic with no drama. Liked them a lot. It
> sounds like your Tiburon might have a pretty tire-unfriendly camber curve.
>
> But the problem might also be that it's just really nose-heavy. That
> McClellan surface is pretty seriously abrasive, too.
>
My Integra is equally as nose heavy as the Tiburon, so front pressures
should be close to what I was running, 42 lbs was what I ran in front (on
cement)
If your car understeers severely at the limit, you will really cook the
fronts at any pressure, I would recommend running the rears either real low
(say 28 lbs) or real high (maybe 50 lbs) to get the rear end to rotate in
the turns. A stiffer rear bar or higher spring rates in the rear will also
help with understeer.
I was able to get about 50-60 runs on the RE71's with a 2650 lb. Integra
Hope that helps..
-Mark
Phil continues:
> When you say they were still rolling over with 53 lbs of air, were you
> checking with shoe polish? You might try +5 lbs with whatever your next
> set
> of tires is and see if that helps. Mark W and I found that his RE71s and
> my
> SP8000s seemed to work best when they were rolling over more than optimal
> for wear--if you put enough air in them so they didn't roll over at all,
> they didn't seem to stick as well. But even with that, mine were good for
> at
> least 100 runs or so and 15k miles. They *did* wear out out first on the
> outside shoulder. Sorry to hear about the tires' untimely demise. I
> wouldn't
> THINK your front toe settings would cause that, but I dunno. And I would
> guess that your camber isn't particularly adjustable, so it seems unlikely
>
> that it's out of spec badly on both sides.
>
Phil's still talking..does this guy ramble, or what? :)
> Not sure if any of this helps at all, but that's pretty much the entirety
> of
> my experience with street tires in general and SP8000s in particular. I
> think I was running about 35 lbs in the front, but my car only weighed
> 1980
> lbs...
>
> phil
>
>
> > > -----Original Message-----
> > > From: Chris Tweney [SMTP:cat@pobox.com]
> > > Sent: Sunday, May 07, 2000 8:54 AM
> > > To: ba-autox@autox.team.net
> > > Subject: disaster at Sacramento
> > >
> > > All---
> > >
> > > I had a terrible shock yesterday at Sacramento's round 3.
> > > After 5 runs (3 runs of my own and 2 of my co-driver's),
> > > both front tires started showing cord on the sidewalls,
> > > right at the shoulder. I'm running Dunlop SP8000s with
> > > 1500 miles and about 30 autocross laps on them, inflated
> > > to 45 psi front/42 rear. After the 5th run I added another
> > > 8 psi each to the fronts; one lap later they were still
> > > rolling over, so we bailed out and drove home very
> > > cautiously.
> > >
> > > So whyinole should near-new Dunlop's give out so quick?
> > > And why would they roll over with such high pressures?
> > > I made sure to check my tire gauge against a couple of
> > > others, and it was in agreement.
> > >
> > > These tires are marginally larger than the stock tire
> > > (205/50 R15 vs 195/55 R15, a +0 fitment that Tire Rack
> > > said would be just fine). Everything else on the car is
> > > totally stock.
> > >
> > > Do I have some heinous suspension problem that would cause
> > > this? Or have I just had the bad luck to get two faulty
> > > Dunlops? Can anybody shed any light on this?
> > >
> > > -chris.
> > > #333 ES Hyundai Tiburon
> > > 'the sad little shark' (at the moment)
>
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