17x9 vs 17x8 vs 18x8
 

Hey all,

Shopping for wheels and tires, before i start i should mention that my gt86 is my DD and track day toy.. so far ive completed 2 track days and a few mountain runs on my new car, stock brakes and tires are done.. im going with a set of good pads and lines before upgrading to apracing sprint kit. As for tires and wheels, im very confused because i keep reading more and more on these forums.

Ive narrowed it down to the fact that i dont think ill run a 245/255/265 for track days specially since im n/a and dont plan to supercharge or go F/I for the next 20000-25000 km. I would like to try out the hankook rs3. Wheel size is whats confusing me.. I'm partial to the look of 17's. What would a 225/45r17 be like on a 17x9.. if it would not be too stretched i would pick that option because in the future with more power a 245 might suite my needs.. for any of you supercharged guys, are good 225's enough grip on a 140ish treadwear tire?

Anyway, what would you guys suggest go with a 225/45 on a 17x9 and have space for a wider tire in the future? Run a 17x8 or 18x8 because even with a supercharger for trackdays a 225 is enough? Does the stretch on a 17x9 possibly benefit the driver?

just start with a 245/40 RS3 on a 17x9 et35-45. 225 on a 9" wheel is silly.

A 225 on a 17x9 would be very stretched. Put it on a 17x8 instead. If you decide to go with 17x9, get 245's.

As far as 18's, 17's clear the sprint kit just fine. 18's are just added weight.

To avoid stretching the tire too much I would go 235s on a 9" wide wheel at a minimum but 245/255s would be more proper.

On an 8" wide wheel you can essentially go 215/225 (expect some stretch) but 235/245 would be more proper in that sense as well.

Barely any stretch with 235/40 on a 9". 225/45 would be fine.

http://tigermack.zenfolio.com/img/s1...75268430-5.jpg

17x8 is a good size for track days with NA cars. Fits anything from 215-235 width.

If you're pretty sure you'll run a 245 in the future, then go with an 8.5" or 9".

a 17x8 can hold most(all?) 245/40 if you want to move up later on. the only benefit of 17x9 is the bigger concave look if you are into that and the potential to get into really big tires.

stiffer sidewalls... better response.

that tire sizing looks really good!

Thanks for the quick responses. I dont want to run 245 while n/a 225/45 on a 17x9 might be the decider.. 17x8 will work fine though hahaha such a confusing decision. @csgmike @csgdavid

245's will feel better on a 9" wheel than an 8", but you can definitely run 245's on an 8".

I have 225's on an 8" wheel, still LOTS of grip.

I wouldn't put 225's on a 9" wheel at all. If you've got a wheel that size, get 245's on it.

I've got 245 MPSS on 7.5's. I'm switching up to wider soon. I want 17x9 all around. My engine is stock and I can still spin them.

8J or 9J? Hard to decide?
Thats why I choose 8.5J for both my stock GT86(225 tire width) and stage 2 STi (245 tire width).

Im set on rpf1, thats not an option :) 235/40R17 is a good option..

I still vote 17x8 with a 235 tire. 245 or 255 would be better suited for a 17x9. Personal opinion only. There are guys in the aggressive wheel fitment thread that are putting 215s on 18x10's. But they're not looking for performance, either. They're looking for stance.

Im looking for 100% performance, dont really care for form. A stretched tire was never bad, Porsche tires are quite stretched from the factory for example..

In that case I would go 17x8/225 or 17x9/245. @ATL BRZ runs 17x9's with 245 tires on his NA track car; you should check out his build thread. Granted, he runs E85 and has the suspension to support tires that wide.


Edit: thread

The rule of thumb for performance is that the tire tread width be +/- 1" of the wheel width, and generally that along that continuum a narrower tire will offer more precise handling and response.

17x9 with a 245/40/17 sounds like what you want.

Highly disagree. 17x9 *can* fit stock suspension.

17x8 is a way better starting point. Start with a 17x8 and 225 tire. See how it is. Worst case scenario you don't like it and can use it as your DD setup and move on.

If you don't like 17x9 worst case scenario is you have to buy aftermarket suspension to fit the tire size you want. And all the issues related to getting aftermarket alignment adjustment parts.

The setup I just described DOES fit stock suspension. with a 45 you need a small spacer...5mm is probably ideal.

Budget is relevant to have for starters

Which wheels are those? they look really good

Weds sport tc105n 17X9 +35... IIRC, they are discontinued.

These are light weight like RPF1, but IMO look better. (they cost more too)

They have a new wheel that looks almost exactly the same though... Weds tc105x. I think they are stronger...

Thanks! What Leonardo said! I have 3 sets now. hahaha

Very nice looking wheels, so "racy" ... pun intended