Porsche Cup takeoffs for HPDE
#1
Porsche Cup takeoffs for HPDE
So, Porsche Cup takeoffs are pretty cheap, would they be ok for an open track day? I'd like to save my Star Specs for autox duty.
27/68-18, if I'm reading it right, are 270mm wide, 680mm tall, and fit on an 18" rim. That would put them about equivalent to a 275/40-18. That's 0.7" taller than the factory tires. Also, does anyone know if these would squeeze onto the factory 8" wide rim?
Feel free to call me an idiot if necessary.
27/68-18, if I'm reading it right, are 270mm wide, 680mm tall, and fit on an 18" rim. That would put them about equivalent to a 275/40-18. That's 0.7" taller than the factory tires. Also, does anyone know if these would squeeze onto the factory 8" wide rim?
Feel free to call me an idiot if necessary.
#4
I was hoping someone has tried previously heat cycled full slick takeoffs though. My experience stops with R-comps.
#8
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Idiot, but it and the overall reply was intended as a joke toward the OP who likely does have fender liners, not you
taller and wider than OE is asking for trouble for a street type RX-8
that siad, I do have a set of 255/40-18 Hoosier rain tires for added throttle control in wet conditions, but then the chassis doesn't see a lot of G loading in that situation
that was on a Stock class vehicle, not sure I could get away with them on my lowered STX class car (which requires 140+ treadwear tires anyway, just a reference point)
.
taller and wider than OE is asking for trouble for a street type RX-8
that siad, I do have a set of 255/40-18 Hoosier rain tires for added throttle control in wet conditions, but then the chassis doesn't see a lot of G loading in that situation
that was on a Stock class vehicle, not sure I could get away with them on my lowered STX class car (which requires 140+ treadwear tires anyway, just a reference point)
.
Last edited by TeamRX8; 06-28-2010 at 05:44 PM.
#11
Correct, I would never consider the 27/68 size even with a 5.12. They use 24/64 on the fronts, that is what I used. Best would be a 17 inch hoosier slick, 43720, that is an inch shorter (24.3). Combine it with the 5.12 and get the best results. The Michelin 24/64 is 25.3 tall (643mm) so not too far off a stock tire.
#13
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Keep in mind, those tires are not R-Comps, they are not street legal. At work, there's a guy who races a 993 cup car. He once said that the jump from R-Comps to full on race slicks was as big for him as the jump between street tires and R-Comps. He's mentioned figures like gaining 14 PSI from cold to warm and that if you hit a curb wrong while they're cold, the tire can pop off a rim.
His name is Jim Walsh, I'll see if I can find one of his mails where he talked about it.
His name is Jim Walsh, I'll see if I can find one of his mails where he talked about it.
#14
#15
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My understanging is the GA/KONI takeoffs are a little harder compound then the R6 but will last longer and still be much faster then a R-Comp.
#18
Another update, I wrote Hoosier about the 275 Koni series tire and this was my response:
Matt,
Good question. Go ahead mount your Koni P275/35ZR-18 on a 18 x 8 rim. The tire fitter should not have much difficulty pinching the 10.3" tread width tire on your 8.0" rim.
The KONI compound is the R6 road race compound and will work fine for your road race HPDE track days.
Hope this helps.
Good question. Go ahead mount your Koni P275/35ZR-18 on a 18 x 8 rim. The tire fitter should not have much difficulty pinching the 10.3" tread width tire on your 8.0" rim.
The KONI compound is the R6 road race compound and will work fine for your road race HPDE track days.
Hope this helps.
Last edited by burglar; 07-19-2010 at 10:30 AM.
#19
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I am suprised Hoosier said to mount the 275's on an 8" wheel but it will fit, that goes against the info they provide on their website. It will work fine for autoX, but you will be compromising side wall stiffness and it will hurt turn in. If you could get a 245-255 you would probably have the same or better results and obviously a 9-9.5" wheel would be the best option. Its only money, right???
#20
Due to the input from this thread I decided to wuss out on the 275s. I grabbed a set of very good condition 245/40-18 BFG R1s for $200 picked up locally. Can't complain about that price.
Now if I could only find some A6 scrubs for a similar deal...
Now if I could only find some A6 scrubs for a similar deal...
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