DG Wrote:
>On impulse, I had stuck a pyrometer into the tires once I had cruised back to
>the pits, and found that, even after 4 runs (and taking into account the
cooling
>effect of my trip back) the tires were still pretty cold - 120 front, 100 rear
-
>on tires that want to be somewhere up around 160-200.
Pyrometer reading should be taken as soon as possible after the run. If you
wait, the only potentially valid data would be the temps across the tread. Did
you take you readings on Saturday morning? Waiting until after impound both
days would be totally useless info. I would say you need readings within 15-30
seconds of exiting the course.
>My G-Forces have been wearing really well, I have nearly 60 runs on them, and I
>expect to see about 20 more, but it's getting near time to buy tires. I have a
>choice to make:
Shhesh! 80 runs on a AWD car that doesn't heat up the tires? Sounds like very
few to me. I have over 135 runs on my Kumho's including 2 Pro's and last weeks
National Tour in Ayer - all on an RX7 TT.
>1) Stick with the G-Force, but drop down a size, to 255-40R17
>2) Switch to Kumho, at 275-40R17
>3) Both, a Kumho 255-40R17
If you like the G-Force, and you think you have heat issues, drop a size and
test. Personally, I think the tire/wheel combo for your application needs to be
smaller.
I love the Kumho's but am considering Hoosier's for 2 reasons. They are
available in my size (245/45/16 - Kumho has been out of stock for 2 months) and
I have gotten some excellent feedback from some BFG drivers who have tried them.
I also feel that the Hoosier is the best 'cold' tire out there. They heat up
extremely fast.
>But here's the $10,000 question - how good are the K-tires, both hot and cold?
I
>understand that a hot G-Force is a better tire than a hot Kumho, but is a cold
>Kumho better than a cold G-Force? Or is it better to stick with the BFGs, but
>move down a size (and so get a lower car and better gearing, but less grip when
>hot?)
I think that all the tires need one run in them to be effective. I would also
argue that on some applications, like high HP - RWD, the Kumho is a better tire
than the BFG all around. Check out all the Vette and RX-7 drivers on Kumho's.
AB
Any thoughts?
DG
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