18" wheels on GT3, what tyre sizes
#4
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Burning Brakes
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I just ordered a set to go with my Forgeline CL wheels, first time for R6's, I ran NT01, MPSC, & R888's on my 996 GT3.
Hossier R6
Front 245/35/18
Rear 315/30/18
Hossier R6
Front 245/35/18
Rear 315/30/18
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Toyo R888
255/35R18 on 18" x 9" CCW C10 wheels
315/30R18 on 18" x 12" CCW C10 wheels
Only other mod to suspension is TPC adjustable rear toe links and track alignment.
The grip is prodigious.
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#8
Race Director
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Hummmintesting specs....stock size is 235-35-19 and 305-30-19 and the guys I run with seem to be mostly using 245-40-18 and 305-35-18 since this keeps the overal diameter right at the same as the stock 19's.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.
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Hummmintesting specs....stock size is 235-35-19 and 305-30-19 and the guys I run with seem to be mostly using 245-40-18 and 305-35-18 since this keeps the overal diameter right at the same as the stock 19's.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.
But keeping close to stock diameters is easy and doesn't involve much math.
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fyi, I worked out the math and the 255/35/18 + 315/30/18 combo should be just fine. It's just over 1% different front/rear ratio from oem. I think the computer is fine with up to 5% difference.
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Similar tires in 19's would cost a bit more. I found a site where a 305 R888 in 19" is only 40 dollars more expensive than the 18". MPSC's probably cost a lot more in 19" than 18"
#12
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I run 245/35ZR18 and 315/30ZR18. I've never been motivated to try anything wider than that, but I've never tried wider either so maybe I just don't know what I'm missing. I've never had any problems with ABS as a consequence of the non-stock tire sizes.
While the Hoosiers aren't cheap, I think that overall I save money because my expensive street tires on my 19" wheels last forever now that I'm not scrubbing them up on the track all the time.
While the Hoosiers aren't cheap, I think that overall I save money because my expensive street tires on my 19" wheels last forever now that I'm not scrubbing them up on the track all the time.
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#14
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Hummmintesting specs....stock size is 235-35-19 and 305-30-19 and the guys I run with seem to be mostly using 245-40-18 and 305-35-18 since this keeps the overal diameter right at the same as the stock 19's.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.
I've seen a few run the 255-35-18 and 315-30-18 to lower the car and gear it down for more acelleration.
I've always been told that when going to an 18" from 19" on the Carrera S and GT3 that I need to keep the overal diameter the same so that ABS and PSM do not freak out.