Convince me...8" vs 9" width

[WytHorse]

Before the flaming starts...
This GT is my daily and I want to keep it relatively low maintenance and simple. I am going to get new wheels and I am targeting 18s in a square setup for longer tread life (full rotations). My target tire is 255/45/18. I like a square or bulging sidewall, so I am leaning towards 8" width...

Currently I'm running the stockers (235/50/18) on 18x9 (+26mm) Drifts which is far from ideal in many ways...

So I want opinions...
Should I go 8 or 9 wide?
Should I stop worrying about running 275 up front and do 9 wide with 275s all around....?
Am I crazy for not going staggered?
Thoughts on OEM wheel quality vs aftermarket...

BTW if anyone has a pic of 255 on 8 wide I would love to see it..

 

[LAllison20]

I had 255/45/18's on a 9 inch wheel, and now sit on 265/50/18s because I wanted more sidewall. Go with 9s

 

[WytHorse]

got any pics of that? That's a big tire... you daily that or is it a fair weather car?

 

[stkjock]

8.5" + 255/45 are perfect

so I say 8.5" or 9"

 

[warpig12354]

I have the same setup as above

 

[skwerl]

My stock wheels are 8.5" wide. 255/45-18 calls for a 9" wide rim but they fit fine on my wheels. I would recommend going with a 9" rim though, because at some point in the future you will want to go a little wider and with the 8" rim you're already too small for the tire.

 

[psfracer]

9.

In this picture the front wheels/tires are 18x9 with 255/45/18s.

 

[LAllison20]

Daily driven. The ride was pretty rough on the 45 side wall, not much of a difference on the 50 side wall, but there is a small rife quality difference.

Sent from my SPH-L710 using Tapatalk 2

 

[302GT]

Currently I have 255/45's on a 8" wheel and there is some bulge. They feel a lot more squirmy than the factory 235/50's the car came with. Just got some 10" wheels for a square setup and hope the 255's don't stretch too much . It'll be a little while before I can afford wider tires. Trust me, I know 255's are not "ideal" for 10" wheels but I've seen 245's on a 9.5 and they didn't look horrible.

I say get 9" wheels.

 

[BruceH]

I've run a 275 square setup before and won't do it again. The roads around here will tramline anything bigger than 255 on my Mustang. If it wasn't for the tramlining I'd still be running them.

Like everyone else says, get the 9" wheels. They will give you more tire selection down the line.

 

[ksconekiller]

I run 9" all around with 255/45R18 tires, and the fit is perfect. Like you, I can't stand the look of a wheel that is even fractionally wider than the tire, and this 9"/255mm combo is just right. Nearly square sidewall with just a hint of bulge. Perfect.

Don't sell yourself short by getting 8" wheels. You will limit your tire choices, and these cars really do look better with more rubber under them.

Good luck!

 

[NUTCASE]

I just got a staggered setup with 255 up front on 9 inch rims. it looks perfect. sidewall is straight up and down and there is just enough rubber to protect the rim.

IMO on these cars unless you are a hardcore corner carver all you need is a decent brand/model 255 tire to tackle some twisties every now and then. any more and all you are doing is spend more on gas and have a level of grip you will rarely use.

you can go bigger out back like I did to get more launch out of a street setup, however it is not necessary and many people run a quality 255 tire out back with success.

and if you go with 10inch out back, get a 285 tire, they are a little taller but I think a 285 would look a little better then my 275s on a 10 inch.

 

[Norm Peterson]

I would never choose to run a 255-wide tire on anything as narrow as 8", and I don't think you'd like losing some of the crisp steering response that your 235/50's on 9's have been giving you.

The earlier GT500's ran 255/45-18 tires on 18 x 9.5" wheels up front (about +45 offset). I'm currently running that setup on all four, and it is an entirely daily-drivable combination. The tire is still wider than the wheel, just not by much.

On 9" wide wheels there will be just a little more sidewall bulge than you see in the thumbnail pic (1/8" or so more). Although it doesn't show up very clearly, the front and rear tires are both about 1/2" inside the fenders, so on 9" wide by +26 offset wheels, you'd be very close to flush with the fender flare - might actually stick out a little (think in terms of a couple of eighth-inches).


Norm

 

[BruceH]

I would never choose to run a 255-wide tire on anything as narrow as 8", and I don't think you'd like losing some of the crisp steering response that your 235/50's on 9's have been giving you.

The earlier GT500's ran 255/45-18 tires on 18 x 9.5" wheels up front (about +45 offset). I'm currently running that setup on all four, and it is an entirely daily-drivable combination. The tire is still wider than the wheel, just not by much.

On 9" wide wheels there will be just a little more sidewall bulge than you see in the thumbnail pic (1/8" or so more). Although it doesn't show up very clearly, the front and rear tires are both about 1/2" inside the fenders, so on 9" wide by +26 offset wheels, you'd be very close to flush with the fender flare - might actually stick out a little (think in terms of a couple of eighth-inches).


Norm

Really? It's a 255/45/18. Lots of sidewall. Nitto says it's ok on a 8" wheel.

 

[NUTCASE]

well I can tell you from having 255/45r18 on my fronts 9.o is best..

 

[Norm Peterson]

Really? It's a 255/45/18. Lots of sidewall. Nitto says it's ok on a 8" wheel.

OK does not mean optimal, only that it meets the Tire & Rim Association guidelines for fitment, and just barely at that (255/45-18 is listed with 8" as minimum recommended width, 8.5" as "measuring", and 9.5" as maximum recommended width).

Squeezing a tire down on to a narrower than measuring rim increases sidewall flexing and heat generation and sacrifices cornering stiffness and steering response.

Stretching it out to 9 or 9.5" reduces the flexing and picks up a little extra in the corners (makes the car drive like it's a little smaller/lighter than it really is). The only "downside" is a slightly firmer ride (but if that's a tire buyer's main concern he probably shouldn't be looking at tire sizes below 50 profile).


Norm

 

[AK83]

I've run a 275 square setup before and won't do it again. The roads around here will tramline anything bigger than 255 on my Mustang. If it wasn't for the tramlining I'd still be running them.

This. I'm running a 275 square setup currently and though the grip is amazing, the tramlining is terrible for daily driving.

 

[Pentalab]

I'm using nitto-555's on all 4 corner's. Fronts are 255-45-18 on 9" rims with a 30mm offset. Rears are 275-40-18 on 10" rims with a 45mm offset. (AM deep dish chrome bullitt wheels). This handles superb...esp with the front camber set at -1 deg... (via steeda front strut mounts, that allow +/- 1 deg of camber).

However, the rears are .4" shorter than the fronts. Last week I swapped the rear 275-40-18's out to a slightly bigger 285-40-18. Now this is even better. Each 285 is now .4" wider....and the 285's are identical height as my 255 fronts.

As a side note, for an experiment, I tried one of the front 255-45-18 tires on the 9" rim.... temp mounted onto the rear......and they look damn good on the back.....with their 30mm offset. The sidewalls end up being exactly in the same place just inside the wheel well as the 285-40-18 on a 10" rim with 45mm offset.

The short answer, use a 9" rim for a 255-45-18. It's perfect. I have a small m90 blower on my 2010, so I use 36 psi on the fronts + 30 psi on the rears. No under steer, no tramlining....and no sidewall flex on front or rears. Plenty of traction.

Jimbo

 

[RetroGT2006]

I would go atleast 9.. I went 18x9.5 on all four corners and run 275/40/18s and I think it looks perfect.

 

[DRock]

I really see no reason to even run an 8" wheel. at all