greatisnate

I bought a 06 GTO a few months ago and im looking at putting some new wheels on it. I wanna know how big and how wide i can go without looking too ridiculous. I dont have a garage so as little modification as possible would be nice.

mark21742

A 9" wide wheel with a 275 tire is about as wide as you can go without having to roll the lip on the quarters. Our cars have an odd size to wheel opening ratio I guess because even an 18" wheel looks small on the GTO, but you'd be pushing it to get a 20" wheel with any kind of tire besides a rubber band on it.....so I would have to recomend a 18x 9 in the back with a 275/40/18, and an 18x8 up front with a 245/40/18.

You will also have to really watch your backspacing on the front because under moderate turning and braking the front tire can hit the strut...(strut rub) is something that needs to be checked and if you are getting close look st getting new tierod ends, radius rod bushing and strut bearings. Whenever you replace a bushing, replace it with s ploy version I know Nelson, and pedestal carry the radius rod bushing and energy suspension carries about all except the RT bushing

greatisnate

awesome man, thanks

leong6gtp

iTrader: (8)

you can go to a 9.5" with 275s depending on the brand some run wider than others. Just cut the lip for extra room.

OrangeGoat

I got 8.5" wide wheels and it rubbed before I put on my drag bags. I think it just depends cause I hear of guys rubbing with wider wheels and some guys don't. What wheels do you have on it now?

mark21742

One big thing is rear spring sag....these car are notorious for it....for instance when I put 1.2" drop springs on mine it actualy raised the back of the car 3/4"

FryZ71

Offset is the key w/ these cars, stock wheels are 8" wide w/ +48 offset. 9" wheels w/ +45 and 275s might squeeze on w/ no fender trimming. 9.5" wheels w/ +45 will require fender rolling/lip grinding. Some guys just put in 5/16 drag springs and/or drag bags to raise the rear and keep the tires from rubbing. If you have deep pockets, companies like CCW can make you set of 10" wheels w/ +54 that will let you run 275s w/ no fender mods and no rubbing.

scphilli

iTrader: (2)

Please do more research before you spend money on a 275/40/18 tire for your GTO. That tire is 1 1/4" taller than stock and will require fender lip mods and suspension mods even with ideal offset wheels.

scphilli

iTrader: (2)

Accurate data and good advice!

mark21742

I know my GTOs, but I did quote my size wrong(I just went out to the garage to check).....I was running a 275/35/18 in the back, not a 40 series, but depending on manufacturer a 40 series "should" fit.
but as said above also different manufacturers tires can vary slightly in width on the same size.

redtan

iTrader: (5)

With rolled/cut fenders, shock extensions and slightly massaged inner fender you can make a 10" wheel with some 285-295s work given the right offset.

That is as far as you can go without major modifications to the rear. Rolled fenders are easy and cheap to do, shock extensions are 80 bux and the inner massaging can be done by yourself if need be.

FryZ71

Or just go for broke and mini-tub the rear and roll some 315s or 335s, haha.

mark21742

Or you can do what I did and tuck 31-18.5 15's on 18" wide wheels. But that takes a little cutting

TriShield

If you have a nice one then don't roll, cut or modify the car to install tires wider than what it was engineered to wear. You'll destroy the resale of the car.

s/c'd cav

iTrader: (10)

the ideal rear wheel is a 18x9 with a 52 offset to fit the 275's

but some tires do run different in width , some are narrow and some are wider , so having the rear cradle alignment checked is a good idea

sporaclic

iTrader: (1)

If you want a wider rear tire just plan on cutting the fenders. Its really not a big deal.
If your going 265-275 You can do a 9.5 45 offset with cutting to the fender.
A 9.5 50offset would be a better option for cutting less fender or squeezing a 285 in the end.

In the front 8" 40 offset is a good option for a 245
also 8.5" 40-45 offset can be done. 45 might be questionable on an 8.5 if your on a stock strut trying to run anything wider than a 235.

Before you invest any money in tires i strongly reccommend you look into your suspension options.
Changing rear springs to a stiffer spring will GREATLY improve your rear tire wear.
Also, your strut mounts and bearings in your front end might be toast which will kill your front tires.
At the very least, all gtos need some form of aftermarket rear setup to keep from needing tires yearly regardless of tire.