gtfoxy

Who has ran that size on a GTO? Looking to put the widest tire possible on the rear.

Any input on back pacing for new rims with this tire would be appreciated.

redtan

iTrader: (5)

Idk if they make 45 tires in that size, it's usually a 40 aspect.

For 9.5" wheels, you need something in the high 40s/low 50s and it will fit with minimal work on either the fender or the inner wall (depending on the final offset...lower you have to work the fenders, higher you have to work the inner wall).

gtfoxy

You're right. I was looking at 255/45's & 275/40's. Title changed, thanks.

I wonder if anyone has put them on to know how much massaging it would take.

2QWK4RU 06 GOAT

iTrader: (1)

275 require several mods to the rear. Fender rolling or trimming are a must and backspace minimum would be like a 45 to low 50's if custom. 45et are most common and available everywhere in a 9.5" width . X-member bushes are also very important. They will locate everything in back and keep out excessive play that can cause rubbing under load.

255 in front can be done, but you will need 35et on a 8.5" width and likely some coilovers to make it happen. 245 is much easier to live with than 255. Either way, 255 is doable, just more work and maybe some more fender massaging up front.

Good luck.

Dyno Junkie

I have used 275/30/19 on both 19" x 9.5" ET43 & ET 50.
Major guard rolling and grinding with ET43.
ET50 only required minor rolling.

Have also run 275/35/19 on 19" x 9.5" ET57.
These require "massaging" of the inner guards.

svede1212

iTrader: (3)

I have put 285s on my stock wheels widened to 9". I run 275s now as they don't make the one I used to use. Widening increases offset to 61mm and I used stronger ARP studs and 5mm spacers to make them an effective 56mm so a little too much is easier to correct than one with too little offset.

As even my 56mm on 9" needed a little inner fender massaging I would think a 9 1/2" would have to be about 50mm to fit really well. IMHO subframe inner and outer control arm poly bushings should be used to tighten the play of the stock rubber ones. A tire that doesn't normally rub but does under hard acceleration or cornering can be helped with bushings by holding the arm where it should be.

gtfoxy

Thanks for the info guys. Sounds like no matter what if I want to try & stuff that tire in there I will need to do some mods.

Not to sound ignorant but what is this et43, et45, et50 et57, etc you guys keep referring to? If that is a reference to back spacing I am not familiar with the nomenclature.


Is there any easy way to raise the rear a tad on top of doing the upgrade bushings?

Rob

iTrader: (6)

Depends on the brand if you need to modify anything. I ran 275/40/17 Nitto Drag Radials with nothing touched and never had a problem.
I then changed to King Springs/Koni shocks/drag bags and ran 275/30/19 Toyo Proxies and same thing, nothing touched the quarters and never a problem. Then installed 265/30/19 BFG KDW2's, never touched nor a problem. Those were as wide, if not wider, than the Toyo's

Felix C

I used 275 Nitto DRs. No rubbing in my case.

Switched back to 245s for DD use.

gtfoxy

Thanks guys. I appreciate the input.

What size rim & back spacing were you using?

ondatrack

iTrader: (15)

When I first bought mine it had 275/40/17 Nitro 555 on the rear with stock 17s. It had Joni shocks and Pedders 5/16 drag springs and they fit with the fenders rolled. It sits too high on the rear for most people but it worked.

gtfoxy

I would like to see a pick of those on a stock rim. I have ran 275/50's on a 8" mustang rim but not sure how 45's would work.

Hey svede, who did the widening on the stock rims for you & how much did it cost?

svede1212

iTrader: (3)

If you mean raising the rear end to prevent rub that's a hack way to do it. 275s can be made to fit without that.

gtfoxy

Without changes to drivetrain & suspension geometry, no.

I was just wondering who widened your rims.

Dyno Junkie

275/30/19 on 19" x 9.5" ET43

Dyno Junkie

Side view or 19" x 9.5" ET43 with 275/30/19

Dyno Junkie

275/30/19 on 19" x 9.5" ET57

svede1212

iTrader: (3)

and no because it degrades handling raising the center of gravity. I got my wheels widened at Weldcraft over by Detroit. I was fortunate enough to get them done years ago when it was only $175 a wheel and a friend dropped them off and picked them up for me so I had no shipping.

EFoxwell

I have 275/35r18's on 18x9.5 et50 wheels and stock suspension with extremely minor rub on the drivers side. Only seems to rub when I punch it in first or second.

The koni's I have sitting in my garage and rear .5" drop HHD the king springs I've been waiting over 4 damn months for will more than likely cure that minor rub so I'll be able to leave the fenders alone.

Dyno Junkie

If the tyre is touching the body the body needs to be modified to suit.
Changing suspension components to "fix" this is simply restricting the movement of the wheel and tyre.