RE: Track tires for 75 3.0V6

["Brian Shorey" <bshorey@xxxxxxxxx>]

back from monterey and vacation, and just catching up..

> While I've been very happy with my Falken GR-B's for hot street
> and the last
> time I was at Sears Point, Rich pointed out that his times
> dropped lots when
> he graduated to the soft compound tires.  I believe his first iteration
> employed Yoko A-008's, and then got the R-1's for a good deal and
> he's very
> happy with them.

even if you don't set up your suspension properly, the soft compound will
drop seconds off your lap times.  the grip, once they're hot, has to be felt
to be believed.

> Enough history.  Now let's say I'm *going* to go the soft
> compound way.  What
> do I gain or lose by wrapping them around my 16" wheels, or even
> get an even
> lower-ratio tires put on a set of BBS 17" wheels?  I'm curious
> about how my
> suspension would react to 205/50/16 or the more
> radical-low-budget-touring-car
> 205/45/17 size?

you need to look at more than just sidewall height.  r1's have different
inner and outer sidewall heights (and stiffnesses), and need appropriate
camber settings to work effectively.

in my experience, you should only look at shorter sidewalls as you stiffen
the suspension - short stiff sidewalls and stock suspensions don't work well
together.

finally, get yourself a pyrometer (sp?).  temperatures across the tire are
important, more so on soft compound tires.  use your readings to determine
proper air pressure and alignment settings.

> At over USD$140 a tire, I can't afford to change out the tires in
> case they
> don't work out!

just run a few sessions, you'll be changing them before you know it.  the
street life is less than 2k miles.  make sure to break them in properly, or
have them heat cycled prior to use, otherwise they'll wear out even faster.

oh, one last thing - i've found that r1's are very sensitive to scrubbing,
more so in my verde than in the lighter spider.  a few hot laps with a lot
of scrubbing and they start to loose grip and wear faster.  a couple of
slower laps and they come right back.

have fun,

bs

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End of alfa-digest V7 #70
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