Wheel Fitment On 69 Mustang

[silver69]

Wondering if anyone knows the widest wheel and tire combo that will fit on the rear of a stock 69 mustang.

Thanks
Silver69

[MBD]

Wondering if anyone knows the widest wheel and tire combo that will fit on the rear of a stock 69 mustang.

Thanks
Silver69

I've seen a 69 Boss 302 with elevens with 315/35s and it filled every inch. The inner housing had to be modified and the outer lips rolled. The car may have had other modifications to the suspension.

I've also seen ten inchers with 295s with slightly more than 6 inches of backspacing (metric Cobra Rs). The owner also had to perform the same modifications to the inner and outer wheelhouse.

There has been a fair amount of articles recommending a maximum of a 9.5 inch wheel with 275/40s. This is supposed to fit without any modifications on most cars and this may be the best compromise if you're building a daily driver.

I may end up going with a 9.5 inch rim with 5.75 inch backspacing and then try a 295 tire first and move down to a 285 or 275 depending on how much room I have.

[67Sally]

This might shed some light on the question. Clickey
W.

[DarkBuddha]

I wish I had something to contribute, but I'm actually interested in the same answer. I know you can get a 275/40 back there with the right backspacing and and a little bit of rolling the fender lip, which is what I'm probably gonna go when it comes time for new tires.

[MBD]

This might shed some light on the question. Clickey
W.

This verifies what the magazine articles report because it shows 275s on 9.5s.

Beyond that commonly accepted size, the widest on the chart is a 9.5 rim with 6" inch backspacing and 285s. Note that it required some "tweaking" to the wheelwells.

[4MuscleMachines]

I'm doing 285's rear on 18" rims with a 9.5" width. The front will be 255's on 8.5" 18's since my 70 has the fenders rolled both front and rear.
What Darkbudda reccomends is also just fine for that car, it will give you a very nice ride quality and peformance characteristics.

[MBD]

I'm doing 285's rear on 18" rims with a 9.5" width. The front will be 255's on 8.5" 18's since my 70 has the fenders rolled both front and rear.

What is your backspacing in the rear?

By the way, we would all love to see some pictures.

[kmcanally]

My 68 coupe has 18x10's (6.38 bs) and 295/35 tires. The lips are rolled and the GW springs are dearched 2". I have about a 1/2" clearance to the leaf spring. Right now this setup rubs so I am going to add 1" arch back into the leafs and hopefully clear with 1/2" lowering blocks...if not then I will remove the blocks.

Since 69/70 cars have bigger wheel wells then a 295 tire with the right backspacing wheel should fit as long as you roll or remove the return flange on the lips.

I read somewhere that the 315 tire on the Boss car mentioned earlier was replaced with a smaller size after the magazine pics were taken. I remember the article and it looked like it was rubbing sitting still (almost as bad as mine)

The max tire size for a given car is always relative to the desired ride height. Obviously the higher the car the bigger tire you can run. Look at the Unique anniversary Mustang and notice the gap between the top of the tire and the fender lip...and its minitubbed. I prefer the top of the tire and fender lip to be pretty close to flush.

I previoulsy had 274/40-17 tires and although I never drove this combo (sold them before the car was drivable) it looked like it would clear without the lips removed as long as the backspacing was correct.

I recommend buying a used junk tire on eBay for trial fitting. Also you can help determine proper backspacing by measuring off of a known wheel mounted on the car.

[MBD]

My 68 coupe has 18x10's (6.38 bs) and 295/35 tires. The lips are rolled and the GW springs are dearched 2". I have about a 1/2" clearance to the leaf spring. Right now this setup rubs so I am going to add 1" arch back into the leafs and hopefully clear with 1/2" lowering blocks...if not then I will remove the blocks.

Since 69/70 cars have bigger wheel wells then a 295 tire with the right backspacing wheel should fit as long as you roll or remove the return flange on the lips.

I read somewhere that the 315 tire on the Boss car mentioned earlier was replaced with a smaller size after the magazine pics were taken. I remember the article and it looked like it was rubbing sitting still (almost as bad as mine)

I was hoping that you would reply, I couldn't remember what size you ended up with but I knew you were pushing the outer limit and were kind enough to share your experiences. Your stang looks great by the way.

I think you're right on the money about the 69/70 maximum; a 10 inch rim with a 295/40 is about all we can go. The 315 didn't look right to me either on that Boss; the tire was too far outboard - although it didn't protrude past the lip.

Since the 69/70 cars have slightly more room than your car, we should be able to squeeze a 10" with 295 with 6 or 6.25 backspacing. The decreased bs would give us a little more distance between the tire and leaf spring and keep the tire from rubbing when say turning into a steep driveway.

Assuming that it will truly fit with no issues, the next question as you suggest would be how low can we go.

[kmcanally]

The 315 didn't look right to me either on that Boss; the tire was too far outboard - although it didn't protrude past the lip

Without minitubs and a coilover conversion he was for sure using up 100% of the space between the leaf springs and the outer wheel house.

I am going to pull the rear tires off this weekend to inspect all of the places I might be rubbing. So far I only know for sure that I am rubbing on the outer wheel house. If I have sufficient clearance on the inner wheel house I might consider going to a coil-over suspension to eliminate the leafs and then narrow the rear an inch or so. I like the bolt in design of the AirRide triangulated 4 link except with traditional coil-overs in place of the air bagged shocks. This might be the best and only way to keep the 295's without raising the car up too high.

[4MuscleMachines]

What is your backspacing in the rear?

By the way, we would all love to see some pictures.

Car is out of town for being finished, I cannot recall but we did carefull measurement and found it would be no problem. The rear has been shortened to the same width as a 65 Mustang. Can't recall the numbers..getting old.

[silver69]

Thanks guys for all the help we are going try fitting this weekend will let you know how it goes.


Joe

[MBD]

I am going to pull the rear tires off this weekend to inspect all of the places I might be rubbing. So far I only know for sure that I am rubbing on the outer wheel house. If I have sufficient clearance on the inner wheel house I might consider going to a coil-over suspension to eliminate the leafs and then narrow the rear an inch or so. I like the bolt in design of the AirRide triangulated 4 link except with traditional coil-overs in place of the air bagged shocks. This might be the best and only way to keep the 295's without raising the car up too high.

Have you ruled out going with a 275 on a 9.5?

[streetrod77]

I have a Maverick. Most of the suspension is off Mustangs. 295's will fit with slight mods & 315's with major mods. This is with 295's.

[kmcanally]

Have you ruled out going with a 275 on a 9.5?

No I have not...I had 275/40-17's on this car prior to being bitten by the bigger-is-better bug. And I am hell f***ing bent on getting them to fit.

However, if I determine that the 295 just will not fit then I will try a 285 on the existing 10" rim. Problem with this is that the only 285 width BFG G-Force KD tire (to match my fronts) is a 30 series. This tire has a side wall that is approximately .70" shorter than the 295/35...so no way jose. So I will have to go with a 275/40 if I do not want to also replace the fronts. And If I go to the 275 tire I will change the wheels to a 18x9 and sell the 10's. If I want 285's then I will have to also change the fronts.

[kmcanally]

I have a Maverick. Most of the suspension is off Mustangs. 295's will fit with slight mods & 315's with major mods. This is with 295's.

That Maverick looks sweet...more pics please!

Those wheel wells must be much bigger than those on my 68 based on how much the wheel in inset from the q-panel. The 295's on my car are about a 1/2" from the leaf spring and even less to the q-panel. What slight mods did you have to do to fit them?

[kmcanally]

I have a Maverick. Most of the suspension is off Mustangs. 295's will fit with slight mods & 315's with major mods. This is with 295's.

That Maverick looks sweet...more pics please!

Those wheel wells must be much bigger than those on my 68 based on how much the wheel in inset from the q-panel. The 295's on my car are about a 1/2" from the leaf spring and even less to the q-panel. What slight mods did you have to do to fit them? And are those 17x10.5" rear wheels you are running?

[MBD]

I have a Maverick. Most of the suspension is off Mustangs. 295's will fit with slight mods & 315's with major mods. This is with 295's.

Wow, more details please. What size rims and backspacing and what's on the front?

[MBD]

No I have not...I had 275/40-17's on this car prior to being bitten by the bigger-is-better bug. And I am hell f***ing bent on getting them to fit.

However, if I determine that the 295 just will not fit then I will try a 285 on the existing 10" rim. Problem with this is that the only 285 width BFG G-Force KD tire (to match my fronts) is a 30 series. This tire has a side wall that is approximately .70" shorter than the 295/35...so no way jose. So I will have to go with a 275/40 if I do not want to also replace the fronts. And If I go to the 275 tire I will change the wheels to a 18x9 and sell the 10's. If I want 285's then I will have to also change the fronts.

I see your dilema. Of course, if you always wanted a modified suspension, you're fine.

If you're like me and budget is an issue, your set up would be perfect to one of us 69/70 vultures. My point being that you always have the option of selling them and starting over. You already know to the 1/8 of an inch what will fit both front and rear.

Just my unsolicited two cents for what it's worth. I've been in your shoes.

[DarkBuddha]

Hey, how about this! Not one mention of a Camare or DSE or anything! Must be a record for longest thread without the word Camaro in it on this forum.