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Re: The tire thing^n

To: Paul and Meredith Brown <racers@rt66.com>
Subject: Re: The tire thing^n
From: John Whitling <alliancemillsoft@worldnet.att.net>
Date: Thu, 22 Apr 1999 14:49:34 -0400
Paul said,

" The idea of requiring a Z rating is interesting.  Not useful, but
interesting.  Apparently, the current tire situation is bad, so we need to
require something we've already got (except for the Hoosier bias tire,
isn't everthing we're using Z rated now???)  I don't get it.  Aren't we all
using the same tires now for solo, IT, and road racing (with the exception
of some of the Hoosiers)? "

My point of bringing this up is not to have every tire company have to 
reengineer it's
existing tire line. It's to keep any tire company from coming out with an autox 
only
tire like the 226 was. You think the tire situation is bad now? In the early 
ninties
it was a real mess. Things are relatively stable now.

The SCCA members have looked into ways of policing tires in the past. It never
happened, mainly because of complex proposals and ... ahem .. politics. If a 
simple to
implement speed rating limitation can help, why shouldn't we try it???

John Whitling

Paul and Meredith Brown wrote:

> It's BAAACCCKKKK.....
>
> Sounds like the G-Force may suffer from some of the same problems as, well,
> any competition tire:  short life in some situations.  That's probably
> mostly a pressure problem, in this case probably too *high* a pressure may
> be as bad as too low.  Ah yes, progress.  I'm now over 100 runs on the
> front tires on the MR2, and they are about half gone.  Yeah, the car is
> light in the front and has ABS, so they've probably got a pretty easy life.
>  And I've been going pretty slow on them at times, which may help too.
> Then again, the reason I've been slow is often due to going to fast.
> Whatever.  The rears won't match the fronts, but it sure looks like they'll
> go well over 100 runs.  That'll be just great as long as the stick doesn't
> go away.  So far they seem to be hanging in there just fine.
>
> The idea of requiring a Z rating is interesting.  Not useful, but
> interesting.  Apparently, the current tire situation is bad, so we need to
> require something we've already got (except for the Hoosier bias tire,
> isn't everthing we're using Z rated now???)  I don't get it.  Aren't we all
> using the same tires now for solo, IT, and road racing (with the exception
> of some of the Hoosiers)?
>
> Granted, the reason the old super-soft BFG 226 didn't have the Z rating was
> that the tread compound would melt.  But I don't think that's why they went
> away;  I found that even on a stock 2000-pound CRX, the 230 (AKA "road race
> tire", yes, with a Z rating) was faster in almost any condition.  The soft
> compound was just too soft, and a lack of adhesion was the result.  Going
> softer isn't likely to help that situation....  Even with those, I got
> 60-70 runs minimum out of a set.  I wouldn't say that's "adequate" or that
> more life wouldn't be better, but that's a far cry from a 1-event tire.  I
> ended up using 230s for almost everything from then on (including a
> somewhat-successful experiment at Salina, despite first-group dirt and cold
> temps).  The 226 was mostly lamented by SP guys, who were overtired to the
> point where they needed the soft compound.  Some of us experimented with
> 226s later on, and except for wet conditions, found the 230s to be
> superior.  Sort of a win-win situation when the longer-lasting tire is also
> faster.
>
> Someone has again mentioned using a durometer.  I have yet to see one that
> is capable of giving repeatable readings.  I'm talking within a 100%
> margin!  I got one intending to use it to track the heat-cycle lifetime of
> 230s.  After taking a series of readings on a set of tires and seeing no
> pattern, I found that I could do the same thing on one tire.  It's a random
> number generator.  There is probably some sort of expensive lab equipment
> that's capable (if used right, which probably includes taking 10,000
> readings and then feeding that through a statistical analysis) but it's not
> hand-held and portable.  If there's a series using it "successfully" they
> probably have just defined it as a success and never bother taking the
> durometer out of its case....  And they've gone to some other method such
> as a spec tire (excellent solution in some situations, obviously not
> workable in Solo) or an exclusion list (not necessarily a hopeless solution
> as long as the competitors and tire companies don't care enough to try to
> find an advantage).
>
> We've hashed this question out over and over and over and over and over and
> over and over and over and over again.  We generally keep getting the same
> suggestions:
>
>         1) seems like it's obvious and perfect - tread wear rating.  Problems:
> you can't really compare the testing they do with autocrossing.  The number
> is relatively arbitrary.  It doesn't take into consideration things like
> tread pattern and carcass.  My own anecdotal experience had by far the
> highest treadwear tires I've ever autocrossed on lasting the shortest time.
>  And having seen other "real" street tires with lots of tread after someone
> has autocrossed on them, it wasn't a fluke.  Another problem is that there
> are plenty of tires out there with "acceptable" treadwear ratings that
> perform nearly as well as our current "R" tires, but with a real street
> tread on them aren't going to last very well autocrossing.  The real killer
> is that these tires are absurdly expensive.
>
>         2) So add them to the exclusion list.  OK, just how far do we go?  
>Some of
> these tires are OEM on cars like Miatas - someone shows up with a new Miata
> and we tell him he can't run in Stock since he's got his OEM Pilots on his
> car???  Yeah, that's a great solution.  Who is going to maintain this list?
>  What sort of agenda are they going to have?  How often are updates
> allowed?  Ultimately I think this would just lead to us having to run
> shorter-lived but more expensive tires.  Yes, the tire companies might just
> support this one....
>
>         3) an "allowable" list.  Sort of a spec-tire list.  Problem here is 
>that
> that's going to be a big list, but if you start by allowing any OEM tire
> you've just defeated the purpose.
>
> Seems to me what we want is something that is fair, and "affordable".  What
> we've got is certainly fair (though I personally liked the days when there
> was just one tire at the top;  at least you know you weren't losing due to
> tires!  Now with at least three choices, who knows?  I can't afford to buy
> sets of all of them and do the testing....)  At least I can go out and buy
> whatever tire I want.  Affordable is a touchy question.  I haven't learned
> the trick of how to sh*t money, so buying tires hurts.  I'd love to buy
> fewer of them.  I'd be happy to support rules that promoted that.  I've
> found that less adhesion doesn't hurt the fun factor;  heck, in some ways
> it helps!  But I'm also not willing to compromise my competitiveness if I
> can help it.  Given that I haven't found that "R" tires wear faster than
> high-end street tires and that they certainly seem to cost lots less, I'm
> not sure that we can do much better than what we've got now.  Especially
> with 3 companies out there with competitive rubber, there are choices.  And
> I'm sure the tire companies are aware of tire life issues.  As much as
> they'd like to be able to sell us 1-event tires, they realize that's not
> going to work.  And I don't think a tread compound that soft would be
> likely to make most of us go fast anyway (based on my 226 experiences).  It
> seems to me that the market will force the tire companies to work towards
> longer-lasting, faster tires.  Look at Kumho's reputation for durability
> and low cost, yet they seem to be quite competitive.  That's a rep that the
> others would love to have.  I'm not all that sure that they aren't all
> somewhat comparable, but Kumho's recent success has got to have gotten the
> attention of the others.  My first set of G-Forces has surprised me a bit
> with their durability.  If they can improve on this....
>
> So I'll ask a question:  what are you trying to accomplish with a rules
> change?    Or to rephrase it, just what is the problem with the current
> situation?  Don't tell me "street tires are cheaper to run" cause I really
> don't think they are, at least not in a competitive situation.  Local
> street tire classes are great.  It would be interesting to look at tire
> life there.  But I don't think that scales up to the national level.
> Forcing us to buy Pilots (or whatever the best legal "real" street tire
> ended up being) would be a significant step in the wrong direction.  Be
> careful what you wish for....
>
> Paul and Meredith Brown
>
> MR2:  "Not the easiest car in the world to work on"


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