Track Tires for the 991 GT3?
#1
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Have any of you guys researched track tires for this car? I wonder if there will be many options in 20", and downsizing to 19" or 18" may be difficult or costly given the CLs.
On our Cayman R, I've corded 5 of the Dunlop tires, at both outside and inside edges, and varying the alignment didn't fix it. We came to the conclusion that the tires are great on road and track up to about 8/10ths, but can't handle more than that for very long. I don't know if the Sport Cup 2 will be much better, and ideally we can get something like the RA1, NT01, R888, etc.
BTW, I put down a refundable deposit on the car to hold a #3 spot, though I'm still considering other options.
On our Cayman R, I've corded 5 of the Dunlop tires, at both outside and inside edges, and varying the alignment didn't fix it. We came to the conclusion that the tires are great on road and track up to about 8/10ths, but can't handle more than that for very long. I don't know if the Sport Cup 2 will be much better, and ideally we can get something like the RA1, NT01, R888, etc.
BTW, I put down a refundable deposit on the car to hold a #3 spot, though I'm still considering other options.
#2
Nordschleife Master
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Nitto NT05 come in 20's though not the correct sizes
255/45R20 vs 245/35R20 on 9J fronts
315/35R20 vs 305/30/20 on 12j rears
255/45R20 vs 245/35R20 on 9J fronts
315/35R20 vs 305/30/20 on 12j rears
Last edited by jumper5836; 09-06-2013 at 09:52 AM.
#3
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I have no idea at all how all those 991 gizmos would react if you decide to substitute wheels or tires or springs or alter shocks valving. it is a breed similar to R8 and GT-R, they all require massive amount of software mods/tuning to make their computerized suspension track worthy. how 991 gt3 will look like - who knows.
#4
Race Director
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Hasn't it almost always been the case that once car makers create a demand by increasing wheel sizes, tire companies follow with appropriate tires? When my 3.2 Carrera came out with 16's, nobody had heard of 17's, 18's and 19's in track tires. Now everybody makes them.
With Porsche and other brands using 20's, we'll soon see a much bigger selection of tires in that diameter.
With Porsche and other brands using 20's, we'll soon see a much bigger selection of tires in that diameter.
#5
Nordschleife Master
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Have any of you guys researched track tires for this car? I wonder if there will be many options in 20", and downsizing to 19" or 18" may be difficult or costly given the CLs.
On our Cayman R, I've corded 5 of the Dunlop tires, at both outside and inside edges, and varying the alignment didn't fix it. We came to the conclusion that the tires are great on road and track up to about 8/10ths, but can't handle more than that for very long. I don't know if the Sport Cup 2 will be much better, and ideally we can get something like the RA1, NT01, R888, etc.
BTW, I put down a refundable deposit on the car to hold a #3 spot, though I'm still considering other options.
On our Cayman R, I've corded 5 of the Dunlop tires, at both outside and inside edges, and varying the alignment didn't fix it. We came to the conclusion that the tires are great on road and track up to about 8/10ths, but can't handle more than that for very long. I don't know if the Sport Cup 2 will be much better, and ideally we can get something like the RA1, NT01, R888, etc.
BTW, I put down a refundable deposit on the car to hold a #3 spot, though I'm still considering other options.
Nitto NT05 come in 20's though not the correct sizes
255/35R20 vs 245/35R20 on 9J fronts
315/35R20 vs 305/30/20 on 12j rears
ah scratch that fronts are 1% but rears are over
Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
305/30-20 3.6in 13.6in 27.2in 85.5in 741 0.0%
315/35-20 4.3in 14.3in 28.7in 90.1in 703 5.4%
255/35R20 vs 245/35R20 on 9J fronts
315/35R20 vs 305/30/20 on 12j rears
ah scratch that fronts are 1% but rears are over
Tire Size Comparison
Specification Sidewall Radius Diameter Circumference Revs/Mile Difference
305/30-20 3.6in 13.6in 27.2in 85.5in 741 0.0%
315/35-20 4.3in 14.3in 28.7in 90.1in 703 5.4%
#6
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if you burn outer edge of NT01 at -3 deg camber it most likely means you are overdriving them OR sway bars are not stiff enough.
#7
Nordschleife Master
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These are my NT01s with -2.0 camber.
Rear tire:
![](http://img163.imageshack.us/img163/2849/mx65.jpg)
Front tire:
![](http://img833.imageshack.us/img833/6697/7a0m.jpg)
I'm going to bump up to -2.4, but I know they will still wear on the outer edge with -2.4. This is on stock sway bars.
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#8
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Definitely limited options in 20” (at the moment). Like Mike said, with McLaren, Ferrari and others going to 20’s, I believe the tire manufacturers won’t be far behind, but I’m planning to get a 2nd set of (19”) wheels to run Hoosiers on-track. Using a similar overall diameter, I doubt there will be a problem.
#11
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Doesn't matter what camber you run, NT01's like to be flipped once on the rim, about halfway through their life cycle. This is how you get stupid life out of them.
#12
Nordschleife Master
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I've been told that flipping doesn't work well, but I believe that may be because they are flipping way past 1/2 way mark. I might try your method. Thanks for the tip!
#13
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Also didn't know your could flip the NT01's they look they couldn't be by their tread.
#14
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The tire is specifically designed to turn into a slick with 2 circumferential grooves. Flip with confidence, and don't go chasing an extreme alignment to try and cure outer wear. These tires grip and part of that is a sidewall that flexes. Just take your time on the out laps to get them up to temp, then go for it. The first couple laps are when most people do the most damage because they don't have patience.
#15
Nordschleife Master