Streldoc@aol.com wrote:
> <snip>
> 1. The tire is 1/2" or so wider (cool) and a bit taller 1/4" (damn). Seems a
> bit heavier even considering it being a larger tire overall.
On my '94 ESP Trans am, my rear 315/35-17 G-Forces were oversized enough to have
clearance problems (where did I put that rubber hammer?), both inner and outer.
:-(
> 2. I used to run hot temps about 30 psi/front and 27 psi/rear on the old R1s.
> Camber is 1.9-2 degrees front and 1.6-1.7 rear. Tire temps would be a few
> degrees hotter on the inside, with even distribution. Tires would cord on the
> inside. Maybe a bit to much camber but didn't want to mess with the setup as
> we were used to the handling and better not to change to much midseason.
> Ended up running (with same car setup) 44 psi front and 41 psi rear with the
> G-forces. Tire temps were even in back and slightly 1-2 degrees hotter on the
> outer shoulder on the front.
Fronts went from 30 to @42psi (however, a bit warmer on the outside), felt OK.
Tried from 40 to 25psi in rear in attempt to deal with a LOOSE rear-end (solid
axle car, but worked great with R1's and Kumhos). 27 seemed to respond best (on
concrete) but temp profile heavily favored outer edge. A driver in another ESP
car
(Dave Schotz) shared nearly identical experiences with pressure set-up in a
similar car. (Rear end did NOT like higher pressures) Camber set-up is -1.3
front,
0 rear... apparently these tires prefer plenty of negative camber.
> 3. Turn in felt somewhat slower...but this may be because grip is quite a bit
> better. This was noticed most in slaloms. You can work the car more
> aggressively though. The car (which is inherently tail happy) felt very
> stable. Slip angle is definitely higher but less than the Hoosier (ride
> experience only). I was able to add a whole turn more rear rebound damping
> without producing rear instability.
No turn-in problems (with the rear end occasionally flailing around, etc!). If
car
continues to be loose, may need to loosen rear bar or tighten front, tighten
front/loosen rear shocks, etc. (or go back to Kumho's!). I agree with the
excellent transitional response (made up for time lost when things got less than
smooth!).
> 4. Tires are probably up to 3/4-1 second faster on a 60 second course...this
> is using comparison with drivers in our area and back to back testing would be
> more accurate.
Time's were surprisingly good in spite of some loose moments (hopefully that can
be resolved over time, but lack of ability to dial-in negative rear camber is
presently a concern).
Dave Young
AZ Region
> Definitely a greatly improved tire for a high horsepower rear drive car.
>Wishit
> came with 4/32 tread depth. I don't however see any evidence that this tire
> will wear out as prematurely as has been alluded to, at least on our car.
>Local
> RX7 driver that corded his first set believes longevity is equal.
> Erik Strelnieks
> SS 93 RX7
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