Best tire size for 91 Fox 18x9 wheels. On coilovers

hassler

Member
Aug 18, 2025
34
10
18
St. Louis
Need new tires on my car. Pretty sure the wheels are 18x9 all around. I thought the back were 18x10 but measurements all look the same.

Currently on the front are: 255/40/18 , yes they rub
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at full steer

Rear size: 275/35/18
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I’ve read that 265/35/18 on all 4 wheels is a good size. Any opinions on this?
 

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I don’t think 265 is a ‘normal’ size for all around, not that you can’t do it. I would think if you’re keeping all tires the same it would be either 245 or 255, or a staggered size like you have now.

But that’s for like 8” wheels. Maybe 275’s all around for a 9” wheel.

Throw up a photo of the whole car I’m curious how 18’s look on a fox in all different styles.
 
There's a difference between what is popular and what is best for overall performance. Staggered wheels and tires are very popular, but a staggered setup adds understeer to a car that was born with a tendency to understeer. If you don't have other mods to compensate for that added understeer, it's something to be aware of if you plan to use your car for performance driving.

The size of your wheels should be somewhere on the back of the wheel.

In general, a 255 is a good size for a 9” wheel. But it is popular to run 275s on a 9" wheel. Keep in mind that, despite being listed as the same size, different brands of tires can vary in size. Look at the specs for the tires you’re considering on Tire Rack. Find the Rim Width Range & the Measuring Rim Width. The MRW will let you know if the tire you want will be pinched or stretched on your wheels. There are advantages and disadvantages to pinching or stretching. You should also compare the Overall Tire Diameter to the tires you have now.

I run 245/40/18 tires on 18x9" wheels on my 1992 GT autocross car. There are some 255s that would fit up front, but I felt the 245 was the best option for my car/purpose.
 
I don’t think 265 is a ‘normal’ size for all around, not that you can’t do it. I would think if you’re keeping all tires the same it would be either 245 or 255, or a staggered size like you have now.

But that’s for like 8” wheels. Maybe 275’s all around for a 9” wheel.

Throw up a photo of the whole car I’m curious how 18’s look on a fox in all different styles.
 

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I have 255/35/18 General G-Max up front with no rub and currently have a 285/35/18 in the rear (previously had 275/35/18s). These are on 18x9 Saleen Reps with a +24 offset. I do run a 8mm spacer in the front as otherwise my rim would hit my coil-over spring (rim rub, not tire rub).

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First pic with 285s, second with 275 rears. 255 fronts in both.

For my son's car we have 18x9 Bullit Reps with a +24 offset and we are going with a 245/40/18 in the front.

My belief is its tire diameter that affects tire rub the most, so the 255/35/18 (25.2" diameter) gives good footprint and not rub. Your 255/40/18 are 26.2" which is almost 0.5" taller than stock - hence rubbing.

265/35/18s are only 25.4" diameter (less than stock diameter), so would give a good footprint and likely less rubbing.
 
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I did 245/40/18 up front on mine, and it is close. Offset of the wheel plays a role too. I had to add a little bit extra camber to my front coil-overs to get it to tuck into the fender on bumps, and had to clock the spindle/strut orientation to full out before tightening up the strut bolts.

But it did clear without contact. I did lower the car a bit after this pic. 245's on a 9" wide wheel do look a little stretched which I wasn't a fan of.
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I have 255/35/18 General G-Max up front with no rub and currently have a 285/35/18 in the rear (previously had 275/35/18s). These are on 18x9 Saleen Reps with a +24 offset. I do run a 8mm spacer in the front as otherwise my rim would hit my coil-over spring (rim rub, not tire rub).

20250824_002626.webp 20220523_170649.webp
First pic with 285s, second with 275 rears. 255 fronts in both.

For my son's car we have 18x9 Bullit Reps with a +24 offset and we are going with a 245/40/18 in the front.

My belief is its tire diameter that affects tire rub the most, so the 255/35/18 (25.2" diameter) gives good footprint and not rub. Your 255/40/18 are 26.2" which is almost 0.5" taller than stock - hence rubbing.

265/35/18s are only 25.4" diameter (less than stock diameter), so would give a good footprint and likely less rubbing.
So you think 265 all around is a solid option? I’m between that option and 245/40/18 front + 275/35/18 rear. I’m unsure
 
I think 265/35/18 is the largest you can go in the front without further mods (flares, custom fenders, etc). Being slightly smaller diameter than stock gives you a better shot at minimal rubbing. It will allow for a fairly wide square set up without impacting your speedo greatly (compared to stock height).

Your other option would be a very good fitting combo as well. Being a 245 in the front will further help with potential rubbing. On my son's car we are going 245/40/18s on the front and currently have some 255/40/18s for the rear, but I am still keeping my eyes open for good deals on 275/35/18s or 285/35/18s. But we will see. Should have his car finished this summer.

What I am saying is either option would be good. The purpose and intended use is probably the most important factor you need to consider when choosing your wheel and tire combination.
 
Think I’m gonna give the 265/35/18 all around a try with Michelin pilot sport 4S. I’m reading that this is the engineered correct setup.

Also “5/16 spacers and steering rack limiter. Should fix my ribbing at full turn. If you have any insight here or this sounds correct, would be greatly appreciated.

Bought the car from a guy who couldnt finish the build. So I’m unwinding everything that was done incorrectly. Your help and quick answers are appreciated
 
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I have the 5/16 (8mm) spacers on the front because with my offset (+24mm) my rims would rub on the coil over spring. No caliper rub issue, just rim to spring rub. I do not have steering rack limiters. No rub on the inner fenders.
 
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