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Discussion Starter · #1 · (Edited)
Hi all,

Seeking advise about my 17" wheel/ tire combo options.
Here's the scoop. This is an auto-x set up (but not race tires UTQG 200 or 180) I want to be able to drive these to the auto-x and home (up to an hour and a half each way)
Have a set of 17" 986 7fr, 8.5r wheels
Thinking about getting 225-45 fr and 245-45 r tires. (Z1 Star Specs or Ecsta XS)

or

I might get another pair of the same rear wheels (17x8.5) to mount up front and run either 245-45 all around or 245-45fr and 265-40r (only available in Z1Star Spec) Is squeezing 265s on an 8.5 rear worth it (sugg. rim range 9-10.5)?

Suspension is stock, though with the motorsport alignment (FR -.8 REAR -1.1) with 205fr on there now, I'm looking for a better total tire/grip with less under-steer, set up. I'm not interested in sway bars etc. (or the bump to another class).

Is it worth it to get the wider wheels up front with this class of tire? Or should I just settle for the 7fronts and 8.5 rears?

Thanks in advance.
 

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Even using either of those street tires, I think it would be worth it to run wider wheels all around, assuming the class you want to run in allows wider wheels. Both SCCA and PCA stock classes allow any optional factory wheels that were available for the car. SCCA even allows lighter aftermarket wheels in stock classes, as long as they are the same diameter and width as the optional factory wheels. SCCA stock classes also allow R-comp tires of any size that will fit on the legal wheels.

I run a Cayman S in SCCA A-Stock, and drive over two hours to and from events on R-comps that have a tread pattern (some R-comps only have grooves around an otherwise slick tire). I run on OEM wheels, but they're 8 and 9X18s. Tire widths are 245 fronts and 275 rears. I run RE-11s in PCA stock class because they come in the same sizes as OEM tires; a requirement in PCA stock.
 

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If you are thinking about getting 2 more wheels anyway and don't mind looking a little funny I would recommend doing what I did. I have the 986 17x8.5s on the front and some 17x9 CUP IIs on the rear (with a 15mm spacer). Right now I run 245's and 275's. See this thread for pics and details: http://www.planet-9.com/cayman-boxster-competition/44590-17-autocross-setup.html

I can't comment on the grip difference in size since I haven't compared directly to anything else.
 

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Discussion Starter · #4 ·
If you are thinking about getting 2 more wheels anyway and don't mind looking a little funny I would recommend doing what I did. I have the 986 17x8.5s on the front and some 17x9 CUP IIs on the rear (with a 15mm spacer). Right now I run 245's and 275's. See this thread for pics and details: http://www.planet-9.com/cayman-boxster-competition/44590-17-autocross-setup.html

I can't comment on the grip difference in size since I haven't compared directly to anything else.
I saw that post, which along with some others, had me thinking about mounting rears up front. I had a line on some 17x9s but waited too long. I don't mind the funny looks. They were on craigslist locally, and I didn't jump fast enough. I might just go aftermarket on 17x9s (for about the same price) instead of getting a whole set of oems and having two sets of extra fronts.

I wonder if anyone is running 265s on 8.5s?

I'm already out of stock class, I'm running ax11 and don't want to be bumped to ax10.
 

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There are some excellent handling tires that would be perfect for the weekend warrior. The Bridgestone RE-11, Dunlop Direzza Star Spec, Yokohama Neova and the Kuhmo XS would all be close to an R compound tire. The best that I have tested is the RE-11 but they are at the top of the list price wise. There are a number of rebates going on at this time.
If I can help let me know.
 

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There are some excellent handling tires that would be perfect for the weekend warrior. The Bridgestone RE-11, Dunlop Direzza Star Spec, Yokohama Neova and the Kuhmo XS would all be close to an R compound tire. The best that I have tested is the RE-11 but they are at the top of the list price wise. There are a number of rebates going on at this time.
If I can help let me know.

From that list it appears only the Bridgestone RE-11 are available in all OEM sizes for 18" and 19". None of the others do that.
 

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Is is AS legal to mix and match different OEM option wheels F and R ?
You mean wheels that look different? Wheels that have different offsets? Please be more specific.
 

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I'm sure looks are legal.. and aftermarket with stock sizing/offset.

I'm talking running wide OEM option 19's up front and maybe the OEM 18's out back. Or 18 front 17 rear.. Something like this. I'm not wanting to debate on whether its a good idea, just curious if its legal.
 
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