Wide Tires on Fox
- Thread starter Reyyyyab
- Start date
- Mar 2, 2015
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Have the rear quarter wheel arche lips cut off and welded ( hardest but best ). The metal is thick but can be rolled too. The inside of the rear wheel tub needs to be beat in in a couple places. You'll need aftermarket lower control arms for the rear. Not impossible to do. The hardest part is choosing the right wheel and tire. All 315 tires aren't the same width.
It's really too much effort for the average guy.
You won't have quad shocks anymore (shocks in my experience with and without, I believe they are better to have), you could have tailpipe issues.
Like sickfox said the fenders will be certainly a problem.
The wheel offset and tire size will have to be dead on.
Most likely they will rub around hard corners.
Could possibly cut the sidewall of very expensive tires.
I think it is stykthyn is the member here that was all about the 315's, although you would have to ask him if he would do it again.
You won't have quad shocks anymore (shocks in my experience with and without, I believe they are better to have), you could have tailpipe issues.
Like sickfox said the fenders will be certainly a problem.
The wheel offset and tire size will have to be dead on.
Most likely they will rub around hard corners.
Could possibly cut the sidewall of very expensive tires.
I think it is stykthyn is the member here that was all about the 315's, although you would have to ask him if he would do it again.
Warhorse Racing
5 Year Member
Using larger tires in the rear creates understeer. Fox Body Mustangs have understeer built in from the factory; adding more will make your car handle worse, especially in performance driving situations.
africansnowowl
Active Member
I have 18x10 in the rear with 285/35 tires. I had to cut the exhaust off for them to fit. I also removed the quad shocks, but I'm not entirely sure if that was actually necessary. Other than that, there are no fitment issues. It's tight, but no rubbing or anything. I'm also lowered on SVE springs. It looks like any wider at all would require a BFH to the inner tub.
That's probably not going to be an easy task.
These cars are pretty old now. Not a lot of mechanics specializing in them.
They could fix them like any other car, but when it comes to customizing, most likely you are on your own.
Nobody is going to want to risk wheels, tires and suspension work and guarantee it works no rubbing.
All you going to be able to go by is experiences here and the issue with that everyone's situation is different.
For example I run a drag radial that is a 275, it is surely wider than a regular 275, probably more like a 285 or even 295 and I have no exhaust clearance issues and I run quad shocks.
Me personally, i'd just scratch 315's off the list.
A 265 or less is usually a pretty simple fit and is notably wider than the 225's that came on the car.
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this is what i have right now. 245. I want to fill in the gap & look thicker. Whats the best tire to get? I would sacrifice handling or whatever to achieve that look.
- Mar 2, 2015
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- 5,816
- 213
When the local drag strips open up track down some local fox racers and find out who does tubbing. Then you could fit the widest tire you want. Suspension has to change....rear shortened ( possibly) but you, can, have that look. There are only very few people that run 315s on foxes without mini tubbing. Mini tubes aren't that hard to do with enough skill....a full tub will cost you.....done right will cost you more.
Most guys stick to the tried and true 275 on a 10 inch wide rim. If you plan to do a bunch of burn outs stick to the 245s....they are cheaper.
Most guys stick to the tried and true 275 on a 10 inch wide rim. If you plan to do a bunch of burn outs stick to the 245s....they are cheaper.
My 85GT has the LMR 10th Anniversary package of 255-40-17 Nitto 555G2s on 17x9 5.95"backspacing on front & 275-40-17 555G2s on 17x10" 6.25" backspacing with .25" spacer on rear. I did roll the back fenders with an Eastwood roller. Before I got this wheel tire package I ran the stock 15x7 10 holes which have 5" backspacing. On the rear I had 275-50-15 Nitto drag radials. I did remove the quad shocks years ago because I had installed aftermarket lower control arms & did not need them. The rear fender were not rolled with the 275-50-15s and there were not rubbing issues. No tailpipe interference with either tire package.
315/35/18 Nittos on 17x10 SC Replica wheels
It was not easy or cheap. First, you need to use longer ARP wheel studs. 1/2” Baer wheel spacer. I have MAC upper and lower control arms. Running Bilstein quad shocks which are very narrow. I have a rear coil over setup with QA1’s locked down at setting 6 or 7 so the suspension doesn’t move too much. Clears the quad shocks and LX tailpipes by about 1/4”. No modifications to fenders or wheel wells. It worked for me but remember, every car is a little different. Good luck
Which brings it all back around to “ it can’t be done unless you minitub the rear”.
If you have to do anything to limit the rebound, or have to drive differently ( i.e. avoid going into an angled drive) just to say you have a 315 tire on your car....you may as well not do it.
I have 315’s on my car, and they fit like they’re supposed too. A Fox fairmont‘s rear wheel tub isn’t any more generous than a fox mustang. I’ve had multiple copies of both cars, ( 3 notches, 6 Futuras) more actually, but these are cars that got the “ treatment”.
I’d say i’m speaking from experience.
I'm all for the biggest ass tire you can jam under the car, and still have some part of the rear suspension.,...plus full articulation. That means everything stock gets replaced, leaving the room for aftermarket upper, and lower control arms. The stock spring gets dumped, as does the stock shock. ( There won’t be any place to mount it after the surgery) A coil over takes care of both jobs in one unit. The rear really needs about an inch on each side cut off so that a 10.5/11.0” wheel will fit fully inside the quarter, to insure that the car doesn’t have to be lifted, or have its suspension travel limited.
The factory wheel tub gets cut down the middle, and the inner gets cut away completely from the frame rail. All of the remaining upper coil mount gets cut away from the inside of the frame rail, as does the axle snubber. the inner portion of the wheel tub now gets a 1-1.5” strip of steel welded/ riveted on to fill the gap, and the inside of the upper frame rail gets a piece of steel/ aluminum angle cut at 1” intervals so that it will follow the contour of the frame rail, and then either riveted or welded to the top of the frame rail. The inside section of the wheel tub gets riveted/welded to that.
When you’re done, you have room for a big tire, and a car that can sit in the weeds with no rubbing, that doesn’t ride like a dump truck, that you won’t have to worry about what type of driveway you can or can’t go up into.
trying to find a rear tire section shot...
If you have to do anything to limit the rebound, or have to drive differently ( i.e. avoid going into an angled drive) just to say you have a 315 tire on your car....you may as well not do it.
I have 315’s on my car, and they fit like they’re supposed too. A Fox fairmont‘s rear wheel tub isn’t any more generous than a fox mustang. I’ve had multiple copies of both cars, ( 3 notches, 6 Futuras) more actually, but these are cars that got the “ treatment”.
I’d say i’m speaking from experience.
I'm all for the biggest ass tire you can jam under the car, and still have some part of the rear suspension.,...plus full articulation. That means everything stock gets replaced, leaving the room for aftermarket upper, and lower control arms. The stock spring gets dumped, as does the stock shock. ( There won’t be any place to mount it after the surgery) A coil over takes care of both jobs in one unit. The rear really needs about an inch on each side cut off so that a 10.5/11.0” wheel will fit fully inside the quarter, to insure that the car doesn’t have to be lifted, or have its suspension travel limited.
The factory wheel tub gets cut down the middle, and the inner gets cut away completely from the frame rail. All of the remaining upper coil mount gets cut away from the inside of the frame rail, as does the axle snubber. the inner portion of the wheel tub now gets a 1-1.5” strip of steel welded/ riveted on to fill the gap, and the inside of the upper frame rail gets a piece of steel/ aluminum angle cut at 1” intervals so that it will follow the contour of the frame rail, and then either riveted or welded to the top of the frame rail. The inside section of the wheel tub gets riveted/welded to that.
When you’re done, you have room for a big tire, and a car that can sit in the weeds with no rubbing, that doesn’t ride like a dump truck, that you won’t have to worry about what type of driveway you can or can’t go up into.
trying to find a rear tire section shot...
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Does 285 fit in the front? Asking bc i found a deal on Facebook & it comes with the set of 315..
315/35/18 Nittos on 17x10 SC Replica wheels
It was not easy or cheap. First, you need to use longer ARP wheel studs. 1/2” Baer wheel spacer. I have MAC upper and lower control arms. Running Bilstein quad shocks which are very narrow. I have a rear coil over setup with QA1’s locked down at setting 6 or 7 so the suspension doesn’t move too much. Clears the quad shocks and LX tailpipes by about 1/4”. No modifications to fenders or wheel wells. It worked for me but remember, every car is a little different. Good luck
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