17x8.5 or 18x9
 

Im almost ready to buy my volk rims, and the question that keeps coming up is whether I should stick with 17 inch rims or up size to 18's. My main focus on the car is performance and I was under the impression that 17 was the sweet spot for wheel size, but others have told me that the 18's are the way to go. What do you guys think?

I believe 17x9 is the sweet spot for weight and grip. Having said that, I run 18x9.5 for looks (also planning FI in the future)

If you care about looks, run 18x9.5. You need 9.5s to get that deep concave face. There's no reason to run 18x9, you'll lose the look but won't gain performance.

If 100% function/performance is your game-- 17x9.

its all preference at that point. if i were you i would look at different tire manufacturer availability and pricing.

Do you like the small wheel big tire look or vice versa? Also going with 18's it widens up the wheel selection as well. 17's currently are quite limited in selection.

I've never heard of going up in wheel size and lower in tire profile as offering any performance advantage. Also, they don't offer 17x9 wheels?

Konig has a few.. those are the choice autox rims, might not look the very best but ify ou want cheap, reliable and wide? second to none

I have wedssport tc105n 17x9 +35 on my FRS. This was even before I got coilovers. So you can run these no problem on stock suspension. Here's a picture with stock suspension

https://www.instagram.com/s/aGlnaGxp...812_1081088320

I guess I'm a little confused. You said you were ready to buy Volk wheels but only have the option of 17x8.5 and 18x9?

Also RAYS makes this https://www.rayswheels.co.jp/product...=en&wheel=57CR

17x9 id run a 17 due to lowered cost. 18s can get pricey fast.

OP clearly doesnt know what he wants lol

Drive car hard, replace tires often, 17" tires cheaper than 18" tires, 17x9 is a standard wheel sizing for 245/40/17 (driven by SCCA and TT rulesets, trickle down effect from people copying fast guys in those realms), that tire works on an 8.5" wheel just fine. Go down to a 17x8 for a cheaper 225/45/17 tire, but I think that'd be too stretched on an 8.5" wheel, it'll work, just preferences. 17" wheels are usually cheaper than 18's too. 235's aren't common to split the difference, especially in fast tire compounds, uncommon tire = expensive tire.


It is less of an issue this decade, pushing for larger diameter wheels offered a lot of performance advantages in the past, it wasn't so long ago that 14" was a 'sporty' wheel (the Miata came on 14" wheels up to the launch of the NB when they were replaced with 15's, the AP1 S2000 had 16's) but we're in a sweet spot right now with most cars offering/accepting 17"-19" wheel options that work great.

Shorter stiffer sidewalls respond faster and more consistently, I believe back in the day before radials were common the lower profiles offered better stability at high speeds. Larger wheels also mean more space for larger brakes which in the early days of discs meant more thermal capacity, stop better = faster laptime.

There's a balance to strike, the car was designed around a 17" wheel with a ~24.7" diameter tire, messing with that formula may make the car feel 'off' as now the bushings, suspension, and chassis are working harder to compensate for the reduced tire flex. It could be worth it if you're going down the well of making your car faster but it sounds like you're just getting started so stick with the 17's imho, spend the money on seat time.

IMHO 17x9.5 is the PERFECT spec. You stick to the 17inch diameter but also get the 9.5 width that is appealing to most without going to 18s. The only problem is that it is very hard to come by. I’m running 17x9.5 +40 TE37SLs on mine.

Stick with the 17s ! Better for performance if that’s what you’re looking for and I’m pretty sure the wheels will look good in either size!

I was thinking of sticking with the current size I have, 245/45/17 and buying another set of the bridgestone RE-71's. The reason I am thinking about going 18 is because it will fill out the car more, but all the mods I'v done on the car had functionality in mind not looks.