Another "Will these fit?": 18" Mustang wheels

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MopaR&D

MopaR&D

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So I did search and was able to find a couple posts by members running 18" Mustang wheels but I wanted to make sure these specific ones would fit on my 1970 Duster. It is of course converted to 5x4.5" bolt pattern all around with '73-up front discs, also has an early B-body 8 3/4" rear so it's a tad wider than an A-body rear axle. I'm mostly curious about the backspacing (these are 5.95"), I've read the 17s can have clearance issues with the tie rod ends which is one reason I want to use 18s, also slightly better tire availability in the sizes I want. Thinking about going 255/40-18 in the front, will those be too big? And 275/40-18 for the rears...

18x10/18x9 Wheels for Ford Mustang FR500 FR05B Black Rims SET
 
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I'm not positive, but I think that you're going to have clearance issues. Some others here may have some insight into what you're up against with 18's.

Here are several photos of what I'm running on mine and you can glean whatever you can from them.

The rears are 17x8, 4 1/2" bs. The front are 17x7 with 3 1/2" bs. The rear tires are 235/45-17 and the fronts are 215/45-17.

The rear is mini tubbed and the leaf springs have been relocated, so I could probably run a deeper wheel without issue. That being said, I have approx.
3/8"-1/2" clearance between the sidewall and the inside of the wheel arch.

The fronts do not have any clearance issues, but if the wheel was tucked up any higher into the wheel well, I'd be rubbing. I think I could get away with either a 225/45 or a 215/55 and be safe, but a 17" maxs me out for my application.

I just took the front of the car off of jack stands so the ride height is a bit high with the fronts tucked under a bit. The shoulder of the tire sits just about at the bottom of the wheel arch and slightly inside of the fender. Sorry I don't have a photo.

I only have my experience to share with you, hopefully this helps. Good luck as those wheels look nice.
 
MopaR&D said:
So I did search and was able to find a couple posts by members running 18" Mustang wheels but I wanted to make sure these specific ones would fit on my 1970 Duster. It is of course converted to 5x4.5" bolt pattern all around with '73-up front discs, also has an early B-body 8 3/4" rear so it's a tad wider than an A-body rear axle. I'm mostly curious about the backspacing (these are 5.95"), I've read the 17s can have clearance issues with the tie rod ends which is one reason I want to use 18s, also slightly better tire availability in the sizes I want. Thinking about going 255/40-18 in the front, will those be too big? And 275/40-18 for the rears...

18x10/18x9 Wheels for Ford Mustang FR500 FR05B Black Rims SET
Click to expand...

So in the front an 18x9 +24 should fit with a 255/40/18 as long as you stay with the 73+ mopar disks. That combo should be about a 1/4” inside of the 275/35/18’s I run on my car. I have 18x9’s with a +35 offset, but I run 13” disks that widen the track 5mm and I’ve run a 3mm spacer so that’s effectively a +27. I don’t think you’d clear 275’s but 255’s should work. With 18” rims the tie rods fit inside the lip of the rim, unlike a 17”.

In the back, what year is the B-body rear? It makes a difference. Also, are your springs in the stock location? I have a 68-70 B rear with 1/2” offset springs, my 18x10s are a +38 though with 295’s.

***Edit***
In the front you will most likely have to either have the wheels machined to enlarge the hub bore or have the hubs on the rotors turned down some to clear the wheels. I had my enkei’s machined to clear the hubs on my rotors.
 
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72bluNblu said:
So in the front an 18x9 +24 should fit with a 255/40/18 as long as you stay with the 73+ mopar disks. That combo should be about a 1/4” inside of the 275/35/18’s I run on my car. I have 18x9’s with a +35 offset, but I run 13” disks that widen the track 5mm and I’ve run a 3mm spacer so that’s effectively a +27. I don’t think you’d clear 275’s but 255’s should work. With 18” rims the tie rods fit inside the lip of the rim, unlike a 17”.

In the back, what year is the B-body rear? It makes a difference. Also, are your springs in the stock location? I have a 68-70 B rear with 1/2” offset springs, my 18x10s are a +38 though with 295’s.

***Edit***
In the front you will most likely have to either have the wheels machined to enlarge the hub bore or have the hubs on the rotors turned down some to clear the wheels. I had my enkei’s machined to clear the hubs on my rotors.
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Dang I didn't know 275s could fit on the front but yeah I'd rather not have to use spacers and such. The rear I have is out of a '67 Coronet it's definitely an earlier one, not a '71-up I know those are a lot wider. I had the spring perches moved 1/2" inboard on each side to line up with the A-body leaves. I think I'll have all 4 wheels machined to fit the car because I tried to test-fit a friend's 18x9" SVE Mustang wheel and it wouldn't clear the centering hub even on the rear axle flange.

The car currently has 15x8" Rallyes with (I think) 4.625" backspacing and 275/60-15 tires and they rub the fenders in hard cornering or over big bumps. I looked up the specs on the 10"-wide version of the wheels I linked and it says the backspacing is 6.37", according to this online calculator that should move the tires inboard just about the perfect amount (0.75")... There's at least an inch of room between the inner sidewalls and the leaf springs currently.

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Alright just placed the order now, can't wait to see how they look on the car!
 
Thanks, but, I'm just the caretaker. The credit is to be given to BaddAss71, as this is his build from 2011.

The fella that had it after BadAss really let it go, so I'm just trying to bring it back to its former glory. New paint, rust repair, wheels and some mechanical issues.

Be sure to post them pics when you're done.
 
MopaR&D said:
Dang I didn't know 275s could fit on the front but yeah I'd rather not have to use spacers and such. The rear I have is out of a '67 Coronet it's definitely an earlier one, not a '71-up I know those are a lot wider. I had the spring perches moved 1/2" inboard on each side to line up with the A-body leaves. I think I'll have all 4 wheels machined to fit the car because I tried to test-fit a friend's 18x9" SVE Mustang wheel and it wouldn't clear the centering hub even on the rear axle flange.

The car currently has 15x8" Rallyes with (I think) 4.625" backspacing and 275/60-15 tires and they rub the fenders in hard cornering or over big bumps. I looked up the specs on the 10"-wide version of the wheels I linked and it says the backspacing is 6.37", according to this online calculator that should move the tires inboard just about the perfect amount (0.75")... There's at least an inch of room between the inner sidewalls and the leaf springs currently.

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Sorry for the delay in getting back to you on this! But I agree, the math on that looks right for the rears with the info from your current set up. And with a 1/2" spring offset you'll have plenty of room for 275's. 285's should actually fit too, as I mentioned I run 295/35/18/s on my Duster on 18x10's but I also had to trim the quarter lip about a 1/2" to pull that off at the ride height I'm at, in addition to the 1/2" spring offset.

There are actually like 6 different widths for B-body 8 3/4's, 4 that are the non-tapered axle type. A '67 is narrower than a 68-70 rear. But like I said with the info on the fit from your current set up I think your wheels will work great. You can take a look at the rear end widths here An accurate 8 3/4" rear axle width list

Yup, in the front 275's are possible without any radical modifications if the backspace is right with a set of 18" or larger wheels. The 18" wheels clearing the outer tie rod ends allows enough backspace for it to be possible. Spacers aren't necessary if you get the backspace right, I'm running without the 3mm spacers now. It was just an experiment as my wheels touch the frame at full lock, but that turned out not to be a backspace issue but rather the steering stops. Or lack thereof actually on a set of QA1 LCA's. Thin spacers are no big deal anyway as long as they fit well and you have long enough studs to still get proper thread engagement.

When you machine the hub bores just remember that you'll probably have to do something custom for a wheel cap unless you machine them to a size for an existing wheel cap (which wouldn't be a bad idea). In the front I used a pull though cap that was the right diameter, cut the end off and epoxied the wheel cap that I'm using in the back.

Here's some pictures showing the wheel cap, and how big the 275's are up front
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Tinmannz said:
Thanks, but, I'm just the caretaker. The credit is to be given to BaddAss71, as this is his build from 2011.

The fella that had it after BadAss really let it go, so I'm just trying to bring it back to its former glory. New paint, rust repair, wheels and some mechanical issues.

Be sure to post them pics when you're done.
Click to expand...

I see, that's a bummer... that car does look familiar though now that you mention it, I've definitely seen it before but 2011 is 9 years ago by now (!!!). I don't get how someone could let a car like that 'go bad' but happy to hear you're bringing it back!


72bluNblu said:
Sorry for the delay in getting back to you on this! But I agree, the math on that looks right for the rears with the info from your current set up. And with a 1/2" spring offset you'll have plenty of room for 275's. 285's should actually fit too, as I mentioned I run 295/35/18/s on my Duster on 18x10's but I also had to trim the quarter lip about a 1/2" to pull that off at the ride height I'm at, in addition to the 1/2" spring offset.

There are actually like 6 different widths for B-body 8 3/4's, 4 that are the non-tapered axle type. A '67 is narrower than a 68-70 rear. But like I said with the info on the fit from your current set up I think your wheels will work great. You can take a look at the rear end widths here An accurate 8 3/4" rear axle width list

Yup, in the front 275's are possible without any radical modifications if the backspace is right with a set of 18" or larger wheels. The 18" wheels clearing the outer tie rod ends allows enough backspace for it to be possible. Spacers aren't necessary if you get the backspace right, I'm running without the 3mm spacers now. It was just an experiment as my wheels touch the frame at full lock, but that turned out not to be a backspace issue but rather the steering stops. Or lack thereof actually on a set of QA1 LCA's. Thin spacers are no big deal anyway as long as they fit well and you have long enough studs to still get proper thread engagement.

When you machine the hub bores just remember that you'll probably have to do something custom for a wheel cap unless you machine them to a size for an existing wheel cap (which wouldn't be a bad idea). In the front I used a pull though cap that was the right diameter, cut the end off and epoxied the wheel cap that I'm using in the back.

Here's some pictures showing the wheel cap, and how big the 275's are up front
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Click to expand...

No worries! Glad to hear these wheels should fit, the calculator showed promising results but it's good to hear from someone who's actually done it. When you say 1/2" spring offset what is that in relation to? For my setup I had the spring perches on the axle housing relocated so the leaf springs still sit in the same location on the body/chassis.

Thanks for linking that list I was unaware there were multiple widths of 1960s 8 3/4" rears. Now I want to go check the width of mine again, I never confirmed what year it was or the exact dimensions aside from spring perch centers to make sure it wasn't a 1971-74; the guy who sold it to me just said it was out of a '67 Coronet.

Good idea for the center caps I hadn't thought about that yet. When you talk about machining the hub bores to a size for an existing cap, are you implying that keeping the bores a slip-fit over the hubs isn't necessary, or do you mean machine the outer edge of the bore slightly larger/smaller to fit a cap? I know on my other vehicles they have aftermarket wheels with a much larger center bore than the hubs so they aren't "hub-centric" and they work fine but they are on a Jeep and old 3/4-ton truck, my Duster gets taken to the track and will see hard cornering on a regular basis so I think having the extra support of the center hub fitting snugly into the wheel bore is a good idea at least on the fronts...?
 
MopaR&D said:
I see, that's a bummer... that car does look familiar though now that you mention it, I've definitely seen it before but 2011 is 9 years ago by now (!!!). I don't get how someone could let a car like that 'go bad' but happy to hear you're bringing it back!




No worries! Glad to hear these wheels should fit, the calculator showed promising results but it's good to hear from someone who's actually done it. When you say 1/2" spring offset what is that in relation to? For my setup I had the spring perches on the axle housing relocated so the leaf springs still sit in the same location on the body/chassis.

Thanks for linking that list I was unaware there were multiple widths of 1960s 8 3/4" rears. Now I want to go check the width of mine again, I never confirmed what year it was or the exact dimensions aside from spring perch centers to make sure it wasn't a 1971-74; the guy who sold it to me just said it was out of a '67 Coronet.

Good idea for the center caps I hadn't thought about that yet. When you talk about machining the hub bores to a size for an existing cap, are you implying that keeping the bores a slip-fit over the hubs isn't necessary, or do you mean machine the outer edge of the bore slightly larger/smaller to fit a cap? I know on my other vehicles they have aftermarket wheels with a much larger center bore than the hubs so they aren't "hub-centric" and they work fine but they are on a Jeep and old 3/4-ton truck, my Duster gets taken to the track and will see hard cornering on a regular basis so I think having the extra support of the center hub fitting snugly into the wheel bore is a good idea at least on the fronts...?
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Oh, I thought you were referring to the DoctorDiff 1/2” spring offset kit. He sells hangers and shackles that are offset a 1/2”, so the spring perches are at 42” c-c. It basically allows the use of the full stock wheel tub. With the springs in the stock location you should be fine with 275’s based on your measurements, but that will be as big as you can go.

For the wheel caps either of those options would work. I think the whole hub centric thing gets blown out of proportion. Plenty of new cars don’t use hub centric wheels. And it’s not like the hub area is guaranteed to be perfectly centered or round either. On some rotors the hubs aren’t fully machined, meaning they’re just as cast. The lugs are doing all the work for holding the wheel on regardless.
 
OK so I figured I'd do an update. I got the wheels about 6 weeks ago, test fit the rears and with some very light grinding on the centering lip on the wheels they fit perfectly over the rear axle "hubs". A few days ago I took one of the front wheels and test fit it, with similar light grinding it slid over the hub but hit the outer edge of the hub 'snout'(?) with about 3/8" gap between the mounting face of the wheel and the brake hub. I'm thinking about just adding some 1/2" wheel spacers and longer wheel studs, would that screw up the offset of the front wheels? I'll also use the opportunity to upgrade to 11.75" rotors I've been wanting to do that for a while.
 
Some pics of trial-fitting the rears, man I can't wait to see these with tires mounted and on the car...

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I wanna do the same with my 72 duster but was hoping to go 17 as I already have good tires but I believe they say you will have tie rod issues, cant wait to see it myself
 
MopaR&D said:
@72bluNblu what do you think about 1/2" wheel spacers on the fronts, are they a bad idea?
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I sent you a DM, but if you’re talking about adding a 1/2” spacer to the 18x9’s that are +24 they won’t work anyway, you’d need to add 13mm to the offset to have enough room to clear the fenders.


72Dust'Ya said:
I wanna do the same with my 72 duster but was hoping to go 17 as I already have good tires but I believe they say you will have tie rod issues, cant wait to see it myself
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Yeah with 17’s the tie rod ends become an issue at about 5.6” of backspace give or take a tenth or two depending on the design of the lip of the rim. Safe bet is no more than 5.6” of backspace with 17’s, which takes 275’s off the table in the front.
 
72Dust'Ya said:
Any update on this?
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Not quite but almost there, I received the rear tires a week or 2 back and just got the fronts a couple days ago. My neighbor who is a big Ford guy wanted to upgrade to wider tires on his Fairmont street machine (has a 32-valve 4.6L Cobra engine, bad little car) so he sold me his 2 rear lightly-used Continental ExtremeContact DWS tires in 255/40-18 for $75 which I'll be putting on the front of my car (I bought new ones in 275/40-18 for the rear). All I'm waiting for now is to get the front wheels back from the machine shop (decided to bore out the hub registers) then I'll take all the wheels and tires in for mounting. Machine shop has had my wheels for 2 weeks now so they should hopefully be finished this week, realistically I'll probably have the tires mounted and be able to bolt on the new wheels next week. Next time-attack session at the track is June 27 so I'm hoping to have everything ready to go by then.
 
72Dust'Ya said:
Ic, Waiting is the worst, Please post pictures when complete
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Sorry for the delay but I never got a call from the machine shop that the wheels were done so that wasted a week or 2, trans also went out I just got done putting the valve body back in last Sunday.

Wheels and tires are now on and they fit perfectly! I couldn't be happier, absolutely no rubbing and the cornering is much improved. I like the ride more too, slightly firmer but much more "planted" especially at higher speeds.

First 2 pics were right after I got them on, the rest were after I moved the rear leaves up a notch on the shackles to lower the rear of the car. That's the top-most hole so I'm thinking my next upgrade will be some Hotchkis leaf springs (these bastard packs kind of suck anyway). Sorry for the bad lighting in the last 3 pics i'll try to take some more during daylight hours.

@72bluNblu thanks so much for your guidance!

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Looks great!!! Any plans for center caps?... I am not 100% sure but doesnt look like you have anything on? You just needed to bore center hole in wheel?
 
72Dust'Ya said:
Looks great!!! Any plans for center caps?... I am not 100% sure but doesnt look like you have anything on? You just needed to bore center hole in wheel?
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Correct no center caps currently. The ones that came with the wheels don't look good to me and the front wheels were bored through but just enough for the hub to fit; it's a bit snug in there I'm not sure if I'll be able to fit a push-through center cap in it. I'll eventually find something though lol. Definitely want to get the ride height sorted out before looking at center caps and such. I should be getting my paycheck in the next couple days I'll most likely get a set of Hotchkis springs and probably some shorter front bump stops so I can turn down the torsion bars without getting too close to hitting the stops.
 
Any Idea how much you had to bore the hub center?.... I measured(cheap harbor freight mic) 70.8 mm hub center on my new rotors an these wheels say 70.6mm hub center , didnt measure the mopar rotors that came with front end but curious now I think about it
 
72Dust'Ya said:
Any Idea how much you had to bore the hub center?.... I measured(cheap harbor freight mic) 70.8 mm hub center on my new rotors an these wheels say 70.6mm hub center , didnt measure the mopar rotors that came with front end but curious now I think about it
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So searching around on here I saw a few mentions of the diameter of the '73-up front disc hubs in inches, converted to mm it was right around 71.5mm. I had the hub registers bored to 71.5mm and the fit is perfect, slightly snug slip-fit; gotta work the wheels around and push them onto the hubs a bit but they do slide on without much trouble which I know will give them some extra support.

I had a friend telling me he uses hub centering rings on all the wheels he puts on his vehicles or else he gets vibrations but he has a Mazda Miata, '96 Jeep Cherokee and '83 Mercedes 300D so those might work differently than classic Mopars. He's also pretty obsessive-compulsive so it might partly be in his head LOL. Still if possible it's nice to have the extra support of the wheels centering on the hubs.

I know for the rear wheels I just took a coarse sanding roll on my dremel to the centering 'lip' and gradually removed material a little at a time until they slid over the 'hubs' on the rear axle flanges. Didn't take much at all I barely removed any material to get them to fit. I couldn't do that on the fronts because the center hub hole wasn't deep enough and the outer edge of the front hubs bottomed with the wheel mount surface still 1/4"+ away from the hub mating surface.
 
@MopaR&D car looks great! Did you ever find center caps? I ask because I am on the same adventure you were with these same wheels. I think I found a solution for the caps as I 3D printed one. :) Just curious what you found?


Couple more questions as well.
1. Did you have them open the center bores all the way through the wheel? Or just deep enough for the hub to fit?
2. did you use a +24 offset wheel in the front?
3. Did you add any further spacers in the front?

The wheels I bought used are

Front: SIZE: 18x9 Tire: 275/35/18
OFFSET: +24 millimeters
BACKSPACE: 5.95 inch
CENTERBORE: 70.8 millimeters

Rear: SIZE: 18x10 Tire: 295/30/18
OFFSET: +22 millimeters
BACKSPACE: 6.37 inch
CENTERBORE: 70.8 millimeters

In the front I have done a BBP swap kit from Pirate Jack (MBM) and so I have the 73+ brake set up. I am hoping to have no issues other than the wheels which will get bored out this weekend. I am planning to have them open the bore only as deep as needed. I am primarily doing that because I don't want the hole to be so large on the front of the wheel.

In the rear I am running an A-body 8-3/4 with 10" brakes, small bolt pattern, with stock location springs.
After a bit of measuring and removal of studs (I was planning to redrill the axles) I realized I needed to move the wheels outboard to get them off my springs. It turned out that it needed to move out 7/8" so I bought 1" thick, 5x4 to 5x4.5 adapters. It also just so happened that I could afford move the wheels out an 1-1/8 before I started getting into the inner wheel tub. (if it were lowered any further)

I have been banking on @72bluNblu measurements in planning and research but none of the posts I stumbled across were spec'd out with standard A-body 8-3/4 rears. So I wasn't entirely sure how it was going to work out until I actually set the tires under the car and took lots of measurements. I should have all my parts in hand by the weekend!

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