Cray Brickyard fitment on a C7 Z51
04-14-2017, 10:50 PM
#21
Advanced
Me neither, that's why I decided to go with what I did just to be sure. I would have liked even wider tires, I'll bet yours look really nice! But didn't want to take a chance with the PTM when I spend so much time at the track. 
ps, Nice ride up Rt 299 for lunch at Cinebar Sam's in Willow Creek if it's still there.
ps, Nice ride up Rt 299 for lunch at Cinebar Sam's in Willow Creek if it's still there.
04-15-2017, 12:31 AM
#22
It's still there but called Willow Creek Cafe (I think). Yes 299 and the surrounding roads 36 & 96 are great roads. I usually ride my motorcycle on those routes. My wife and take the vette up to The Straw House @ Big Bar (she doesn't like the bike) for Sunday breakfast. 299 is beautiful mountain road to drive drive. You must have lived around here.
Been riding motorcycles for 46 years almost continually. Current stable-
2003 Honda Goldwing
2011 Kawasaki Concours
2006 Suzuki GXR-R600 (Track bike.)
Last edited by bikevette; 04-15-2017 at 12:35 AM.
04-16-2017, 09:56 PM
#23
Intermediate
OK, OP here. 2015 Z51. Here's what I ended up with. Cray Spiders. Front 18/9.5/56 and Rear 19/11.0/76. Front Toyo R888R 265/35/18. Rear Toyo R888R 305/30/19.
The reason I picked these tire sizes was that I wanted to keep the ratio between the front and rear tire heights the same as stock for PTM management, especially as these tires/wheels are only for track days.
If you look carefully you can see a minor amount of tire sticking out past the wheel well. About 1/3" or so.
The only minor glitch is that at full steering lock the front tire rubs a little bit on the plastic wheel well liner on the inside forward of the front wheel wells. Anything less than full lock there's no rubbing at all that I can see or hear. Will know for sure next time I hit the track, but everything looks good so far. Even on a very tight set of turns at The Ridge Motorsports Park- turns 13 and 14 I don't go full lock.
The reason I picked these tire sizes was that I wanted to keep the ratio between the front and rear tire heights the same as stock for PTM management, especially as these tires/wheels are only for track days.
If you look carefully you can see a minor amount of tire sticking out past the wheel well. About 1/3" or so.
The only minor glitch is that at full steering lock the front tire rubs a little bit on the plastic wheel well liner on the inside forward of the front wheel wells. Anything less than full lock there's no rubbing at all that I can see or hear. Will know for sure next time I hit the track, but everything looks good so far. Even on a very tight set of turns at The Ridge Motorsports Park- turns 13 and 14 I don't go full lock.
Or, you could swap those 18/9.5/56 for some 18/9/50 Cray Spiders instead. They won't rub at all, but will stick out 1/4" more, and will keep you from going custom (to get the extra 1/2" width that would really be ideal) or having to run spacers.
In fact, I think this exactly the setup I am going to order. Same tires and wheels as you, but with the 18/9/50 fronts instead of the 18/9.5/56. I hope somebody can talk me out of this, though, because I am lusting after the HRE P101 wheels in Brushed Dark Clear.
http://www.hrewheels.com/wheels/series-p1/p101
OEM rear to front tire height ratio is 1.0348 (3.48%- 26.7" rear/25.8" front).
New combination front to rear height ratio are 1.0355 (3.6%- 26.2" rear/25.3" front). Using other combinations, e.g. Toyo 315/20s rear and Toyo 305/19s front would have equated to 1.008 (.8%- 26.2" rear/26.0" front vs. 3.48% OEM). Maybe I'm being too OC, but maybe not. Plus, if I'm getting a minor amount of full lock rubbing, unless you can find similar wheels with a smaller offset, I would think that the rubbing would be worse with a 305 on the front. But then you're going to get a tire sticking much farther out of the wheel well with a smaller offset.
New combination front to rear height ratio are 1.0355 (3.6%- 26.2" rear/25.3" front). Using other combinations, e.g. Toyo 315/20s rear and Toyo 305/19s front would have equated to 1.008 (.8%- 26.2" rear/26.0" front vs. 3.48% OEM). Maybe I'm being too OC, but maybe not. Plus, if I'm getting a minor amount of full lock rubbing, unless you can find similar wheels with a smaller offset, I would think that the rubbing would be worse with a 305 on the front. But then you're going to get a tire sticking much farther out of the wheel well with a smaller offset.
I think this would probably be close enough, but you have convinced me that your choice is closer to OEM and I am also very concerned about PTM, so I am going to go with an 18/19 setup instead of the 19/20.
Regarding the TPSMs, I installed new ones before I brought the wheels in to have the tires mounted. Part number 13598775. I brought the tire/wheel set home in the back of my truck and installed them in my garage. After starting the car, the DIS showed tire pressure displays, but they were the old tire pressures, as I checked the tire pressures on the old and new sets. So I put the old tires behind a concrete wall and the car is still reading them, not the new tires. So then I let the car sit for 20 minutes idling, then drive it. After about three minutes the DIS flipped over to read the new tires. Piece of cake.
Last edited by Rtmoore4; 04-16-2017 at 10:00 PM. Reason: Added HRE wheel comment