GTOdave

ok guys i have and 04 gto with longtubes no cats, daiblo tune, k&n coldair and i was wondering if there is a way i can put a fatter tire on the back??? bc the biggest i can go with right now is a 255/45/17....i tired a 275/45/17 and it rubbed soooooo bad on the back fender...soo how i get different shocks on the back to raise it in or what...some one help me bc almost when i go to the track i cant get and traction and i was a wider tire but it just dont fit...:/ someone help me out thanks!

bigredgto

you need to roll the rear fenders for a 275 tire. you might also need to install drag bags as well into the rear springs. rolling the fenders is easy with the right tools and drag bags aren't hard to install either. do some research on the two and you should be good to roll with a 275/40/17 (not a 275/45/17 as you stated earlier, as that's the wrong size)

breze84

you can do 1 of 2 things or both to fit 275 tires with no problems....
1. You can get drag bags to stiffen the rear from squat.....
2. Grind the inner fender lip or roll it, I would grind instead of rolling it....
3. Do both...

svede1212

iTrader: (3)

jacking up the back end looks like crap and takes away from the car's handling. to do it right let's you get pretty good tread back there without sacrificing the other things. first thing about tires is that what you want is the maximum tread width and not just a number. tires like Nittos let you tell people you have "275s" in the back but they are about a inch narrower than 275s of another brand like BFGs so don't get hung up on the tire number.

several things should be done. first thing is your wheel offset and width. the stock 8" rim is made for 245s or maybe a touch more but wider tires fitted on there will bulge the tires out so they can rub not to mention making the tread not lay right. a wider wheel flattens the sides and makes the tread contact the road properly. a larger negative offset pulls the tire more towards the center of the car away from the fender where there's more room. i sent my back wheels off to Weldcraft and had them widened an inch for bigger tires. that also increases the offset.

fender rolling or cutting buys you some room on the outside. i prefer rolling as if done right it keeps the strength in the fender and doesn't require touching up the paint. both methods can give you problems if not done right. the paint can crack or you can get a wavy fender with rolling and cutting also needs care so you don't overheat the paint plus you have to seal it so it doesn't rust. rolling isn't hard. i did it with a borrowed tool in about a half hour for both sides gently heating the paint with a paint gun so it wouldn't crack.

it's also best if you stiffen up the rear control arms with poly outer and especially inner control arm bushings. the inner bushing has voids in it and allows the control arm to flex a little bit so if you're tight on clearance you may get rubbing on hard turns.

i also added 5mm wheel spacer to bring it back out a touch and replaced the wheel studs with ARP Corvette studs which are stronger and longer. with all these things done i was able to get 285s in the back and she's on 20mm drop springs. the wheels can now do a full travel to the bump stops without any rubbing.

picture of the 285s before the drop springs...



with springs

SIC GTO

I had 275's and they fit no problem didnt have to do a thing!

svede1212

iTrader: (3)

275 Nittos? as i stated in my post above they really aren't like a real 275 but are in name only.

besides the safety aspect of having the proper wheel there's the actual "rubber meets the road" and sometimes the fender. here are 2 pictures showing tires of the same tread width. one is on a 8" rim and the other is on a 9" rim. you can see how the tire bulges out causing improper tire contact to the road (and thus losing the benefit of a wider tread) and pushing farther out towards the fender causing it to rub.

8" wheel



9" wheel

SIC GTO

no mine were firestone wideovals

breze84

+10 on that...

chance575

pedders makes taller springs or a replacement stock height one will make your car taller, the factory springs sag from the time of delivery

svede1212

iTrader: (3)

not if you put drop springs on

GTOdave

so i pretty much have to get wider back trims in order to get wider tires on bc i have the stock chrome 8 in ones..and what else i need to do with it? lets make this short and sweet..

05TurboCGM

Here's the simple answer:

Buy wider wheels and roll/grind your fender lips. Or pay a shitload on some custom wheels and you won't have to cut the fender if you don't want to. You're done.

RacerXLs1

iTrader: (14)

I didn't have to do anything to mine. But i did have some 16 inch rims off a Camaro on my car. But i would either get some drag bags. There cheap 100 BMR has them.

SIC GTO

Man I dont get why everyone acts like a 275 is huge or something you can run it without doing a damn thing me and my friend both have them in several diff brands and they dont rub!
Im on stock 17's with stock suspension and not one problem!
hell im bout to throw on 285's soon how it sits AND IF its does rub with 285's I will get drag bags.

batboy

iTrader: (6)

A 275 is too wide for the stock 17" wheel, why would you try a 285? I ran a pair of Nitto 275 on stock wheels for one summer and the inner/outer edges of the tires pulled in so much I probably lost an inch of contact.

I installed Pedders springs/shocks and still had to grind the inner lip a little for my 17X9 wheels and 275 Mickey Thompson drag radials.



This is what it looks like when I'm launching:

tmiller

So get 275/40/17s.

I run 275/40/18s with zero problems and don't have to run a "REAL" 275 nitto that won't perform in all real world conditions like the Dunlops I run.

GeneralPatton

iTrader: (1)

I know many people like the dropped look, my previous car had a 2" Drop but with my GTO I will be going with the 0" Drop or the 5/16" Raise, and then drop the front 1" for a racked look. I love the racked look on V8's so that will help my situation when come time for wider wheels and fatter tires.

GFORCE also sells lower shock extensions which give you about 3/4" more room for tires
http://www.ls1gto.com/forums/showthread.php?t=335973

but you will still need to play with the fender as everyone else mentioned.

SIC GTO

Idk dude I had 275/40/17's with 0 problems at all even at the track, but I no people say a 275 is too wide for the stock width of the rim but I didnt find a actual problem so idk why some people have problems and some dont?

GTOdave

alright...well i need tires so i think im just gonna get the 275 40 17s..just to see how they work..bc i hear some ppl say they work...some ppl say they dont..so im gonna find out my self.

GTOdave

i also got a question...on my goat..my throttle body it says ls1 and im prettty sure mine has the ls6 intake bc 04 and up come with it..but then again my budys gto says ls6 on the throttle body..y?