Fox 18x9"s on a 90 gt. Will it work?

Brando30

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I've got a stock 90 gt. Will 18x9's fit?
I'm sure there will be a little massaging required...any tips before I go spend a few thousand on suspension parts and new wheels and tired would greatly be appreciated!
 
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FastDriver

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Yeah, they should. You'll want about 6.5" back spacing. Go with a 245/40/18 up front, and a 275/35/18 out back to get closest to stock diameter. You could maybe squeak out a bit more on both, but you're on your own at that point. Try flipping the quad shocks, which should give you the clearance you need, and if they don't rub anything leave 'em be. You may have to roll or cut the rear fender lips and take a hammer to the inner tub as necessary. It won't take much. If the quad shocks do rub, then you can remove them, but that may, probably will, induce wheel hop under heavy acceleration with a sticky tire. That takes parts and knowledge to get rid of, and we can help you, but it may not be worth it to get adjustable control arms, set pinion angle, reinforce torque boxes, etc... Or, if it's just a cruiser/show car, then you might not care to launch hard.

I've got 255/40/18s up front, and 285/40/18 on one of mine with stock tubs, but then again a lot of stuff has been done to make that work, and they still rub a bit up front on full compression.
 
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RaggedGT

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I've got a stock 90 gt. Will 18x9's fit?
I'm sure there will be a little massaging required...any tips before I go spend a few thousand on suspension parts and new wheels and tired would greatly be appreciated!
Yeah, they should. You'll want about 6.5" back spacing. Go with a 245/40/18 up front, and a 275/35/18 out back to get closest to stock diameter. You could maybe squeak out a bit more on both, but you're on your own at that point. Try flipping the quad shocks, which should give you the clearance you need, and if they don't rub anything leave 'em be. You may have to roll or cut the rear fender lips and take a hammer to the inner tub as necessary. It won't take much. If the quad shocks do rub, then you can remove them, but that may, probably will, induce wheel hop under heavy acceleration with a sticky tire. That takes parts and knowledge to get rid of, and we can help you, but it may not be worth it to get adjustable control arms, set pinion angle, reinforce torque boxes, etc... Or, if it's just a cruiser/show car, then you might not care to launch hard.

I've got 255/40/18s up front, and 285/40/18 on one of mine with stock tubs, but then again a lot of stuff has been done to make that work, and they still rub a bit up front on full compression.
Hey @Brando30
I deleted your question (which is the same question you asked here.) from the thread explaining the purpose of that section of the forum.
@FastDriver gave you the best,most detailed answer and advice I think you will get on the 18’s subject. He’s a knowledgeable guy. I’d trust his advice
 
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Brando30

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Thanks guys. I'm still new to stangnet, so I haven't quite figured out the navigation. I'm restoring my ride and the help is much appreciated! Thanks again
 
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Wayne Waldrep

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I ran the same as @FastDriver except for 35 series on the rear. No quads. Rolled fender lips. Massaged inner fenders with large hammer years ago for slicks so that was already done. That's the only two things I had to do on the rear. Zero mods up front at that time. The car looked great with that size. Was it a perfect fit with never a rub? No. But it was good.
 
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FoxMustangLvr

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I've got a stock 90 gt. Will 18x9's fit?
I'm sure there will be a little massaging required...any tips before I go spend a few thousand on suspension parts and new wheels and tired would greatly be appreciated!
What suspension parts are you buying? I can't really think of anything with suspension mods that would negate 18x9's but I just have to ask anyway.
 

Ultra90GT

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Yes I had 18x9 saleen reps on the front of my 90GT from LMR...245/45/18 tires. Rubbed just a touch at full lock but other than that, no issues....18x10s rear with nitto 555r 305/35/18
 

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FastDriver

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What was your backspacing and any mods? Did you roll your fenders? Did you have to "modify" the inner tub? I'm guessing yes to all.
 

Mstng93SSP

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For me nothing rolled, nothing modified, all I did was flip my quad shocks. I have fox length rear 5 lug axles. Don't remember my backspacing...they are the saleen style wheels from American Muscle.
 

Blown88GT

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Don't remove the quads. Ford didn't put them there for nothing. They never spent an extra $1, if not absolutely necessary.
Their motto was "build them cheap & as fast as you can".
 

Ultra90GT

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I've never ran quad shocks on any of my Mustangs and never once had an issue. Nobody I know with a box body runs there quad shocks. They are only there to keep the rear end from rotating up and down but a good set of control arms and poly rear end housing bushings eliminates that
 
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FastDriver

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I've never ran quad shocks on any of my Mustangs and never once had an issue. Nobody I know with a box body runs there quad shocks. They are only there to keep the rear end from rotating up and down but a good set of control arms and poly rear end housing bushings eliminates that
Kinda sorta... definitely helps, but no guarantee. Another thing to get right, perhaps the most important, is pinion angle, which can't be done unless you're lucky or you have adjustable control arms. The point is, if they fit, you must acquit... er... you should just leave them in place as they can only help. Or if you've got a drag radial or slick handy, make a few test passes and see if you get wheel hop. Or, just throw 'em on the shelf and if you get wheel hop, you can put them back on. Just because you don't get wheel hop on an all-season doesn't mean you won't with a stickier tire. I've had plenty of foxes without quads and without wheel hop. Then again, the one I just bought does wheel hop (stock suspension except adjustable shocks), and I've found free quads and plan to put them on it.
 
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Ultra90GT

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I've always ran adjustable uppers without quad shocks and set pinion angle on -2....its just always worked for me