Test fit Vision 18" wheel today

[JoesEdge]

I started testing fitting the wheel I ordered from Vision Wheels.

These are the Vision Legend 5 172 Wheels which could be found here.

I only ordered one to test fit. If I like the fit, I'll keep it and order the rest. I haven't decided if I'll stick with the same size front and back, or if I'll stagger the wheels and go wider in the back.

The advantage of running the same size front and back would be the ability to rotate the tires, but staggering them would look cool! ;)

Here's the wheel specs:

Part Number: 142-8865GM32
Size: 18" x 8.5"
Bolt Pattern: 5 x 4.5"
Center Bore: 83 mm
Backspacing (Offset): 6.0" (+32 mm)

I didn't have enough daylight to test fit in the front, so for now I have only test fit on the rear axle. In the rear, I am running a '69 B-body 8 3/4 axle with the spring perch moved in to A-body width.

I have measured to have 1 1/4" of space between the wheel lip and the leaf springs. If I do stagger them, the 9.5" wide wheels will have 3/4" more backspacing. That would leave me with about 1/2" of space between the wheel lip and leaf springs. I'm not sure if that's enough space or not.

I plan on going with 255/40 all the way around on the 8.5" wide wheel or 275/40 on the 9.5" wide wheel for the back and 255/40 on the front.

So you think I can stuff the 9.5" wide wheel back there with 275's?

 

[72Dart6pack]

You need to know the cross section of the tire. Most tire manufacturers will tell you the the width of the tire at different pressures and rim width. Start doing some homework.

 

[72bluNblu]

The 9.5’s with 275’s should work, they may need a small spacer. They’ll overhang the rim by about a 1/4” or less, most of the 275’s have a section of 10.9”
or 11” and the 9.5” rims are 10.5” edge to edge. Which would leave you with about a 1/4” of clearance. Which is pretty tight, but that’s about all I’ve got. An 1/8” spacer and you’d be fine for sure, and the center registers on the axles are taller than that still.

The 255’s would be a piece of cake, and being able to rotate the tires is a nice benefit. The 275’s will be tight everywhere, but they do fit most Dusters. Better to have them tight to the springs and adjust with a small spacer if need be than to have them too close to the quarters.

 

[JoesEdge]

The 9.5’s with 275’s should work, they may need a small spacer. They’ll overhang the rim by about a 1/4” or less, most of the 275’s have a section of 10.9”
or 11” and the 9.5” rims are 10.5” edge to edge. Which would leave you with about a 1/4” of clearance. Which is pretty tight, but that’s about all I’ve got. An 1/8” spacer and you’d be fine for sure, and the center registers on the axles are taller than that still.

The 255’s would be a piece of cake, and being able to rotate the tires is a nice benefit. The 275’s will be tight everywhere, but they do fit most Dusters. Better to have them tight to the springs and adjust with a small spacer if need be than to have them too close to the quarters.

You're right about the lip to lip width! I had forgotten about that. So maybe I'll have about 1/4" of gap between the tire and the leaf spring.

A 1/4" is pretty tight, but to be honest I probably had about 1 1/4" to 1 3/8" of space. I just went with the smaller number to be safe.

I already have a set of billet 1/4" spacers that are hub-centric. Speaking of which, I probably should get some hub-centric rings that goes from 83 mm to 71.5 mm.

 

[JoesEdge]

so I test the wheels in the front yesterday. well, 18's definitely clear pretty much everything and even with 6 inches of backspacing I can say that the rim does not hit the stock upper control arm. BUT, I guestimated that with 26" tall tires the tire will be rubbing against the frame rail. I don't know how you guys with deep backspacing do it and not hit the frame rail.

 

[72bluNblu]

so I test the wheels in the front yesterday. well, 18's definitely clear pretty much everything and even with 6 inches of backspacing I can say that the rim does not hit the stock upper control arm. BUT, I guestimated that with 26" tall tires the tire will be rubbing against the frame rail. I don't know how you guys with deep backspacing do it and not hit the frame rail.

It really depends on the steering stops and the height of the tire. On my car the tires just touch at full lock, that's with 25.6" tall tires and a 6.1" backspace. But the steering stops on the lower ball joints are not all the same. I compared a bunch of old ones that I had and found that the height of the steering stops weren't very consistent, so, that effects where full lock actually is. You just have to kind of thread the needle between having enough space to the fender and the frame rail. Being too close to the frame rail is better, you can make some adjustments with small spacers.

In my case, I don't worry about it too much. With my 16:1 manual steering I'm very rarely at full steering lock anyway. If I were more concerned about it I could probably put a little weld blob on the steering stop, I don't have any more room to the fender to give up.

 

[JoesEdge]

It really depends on the steering stops and the height of the tire. On my car the tires just touch at full lock, that's with 25.6" tall tires and a 6.1" backspace. But the steering stops on the lower ball joints are not all the same. I compared a bunch of old ones that I had and found that the height of the steering stops weren't very consistent, so, that effects where full lock actually is. You just have to kind of thread the needle between having enough space to the fender and the frame rail. Being too close to the frame rail is better, you can make some adjustments with small spacers.

In my case, I don't worry about it too much. With my 16:1 manual steering I'm very rarely at full steering lock anyway. If I were more concerned about it I could probably put a little weld blob on the steering stop, I don't have any more room to the fender to give up.

Good to know. I wonder how much weld it would take to make it so the tire does not hit. Also, how much of a turning radius would I lose. I mean, would I still be able to make u-turns.

This exercise actually made me recall a conversation I had with Bill Reilly from Reilly Motorsports. He said that these cars have "forklift" like steering. Meaning, they turn an excessive amount. Now I see what he means.

So, where are the steering stops? Do you have a picture? I guess when it stops raining I could turn the wheel and get under there and look.

Maybe I could play around with this. I'm kinda determined to make this work because, to me, they looked so damn good.

 

[72bluNblu]

Good to know. I wonder how much weld it would take to make it so the tire does not hit. Also, how much of a turning radius would I lose. I mean, would I still be able to make u-turns.

This exercise actually made me recall a conversation I had with Bill Reilly from Reilly Motorsports. He said that these cars have "forklift" like steering. Meaning, they turn an excessive amount. Now I see what he means.

So, where are the steering stops? Do you have a picture? I guess when it stops raining I could turn the wheel and get under there and look.

Maybe I could play around with this. I'm kinda determined to make this work because, to me, they looked so damn good.

The steering stops are on the lower ball joint, they contact the LCA at full lock.

As for how much it would take, it depends on how much interference you have. It wouldn't take much, the steering stop is rotating around an axis, so, what you're modifying works in degrees. Even a small increase in the steering stop length could limit the turning radius by a couple of degrees, which would change the clearance quite a bit. That's why found it interesting that the stops weren't very precise when I compared a bunch of old ball joints- even a 1/16" change at the stop would be significant, and there was that much variation between different ball joints.

It would change the turning radius of course, but, because these stops weren't very precise it's hard to tell how much your car would change compared to say, the factory spec. Your car could already have a tighter turning radius than what the spec was if the stop is a little undersize. How much the turning radius changes would depend on how much you add to the steering stop.

I went and looked at this after I installed the 275/35/18's on my car. I had been using a lot of info from 72BBswinger, and my wheel specs were pretty much identical to his. But on his car he had plenty of room to the frame, while on mine I had contact at lock. Again, not a lot, the tires just barely touch the frame at full lock. After looking into the steering stops, I realized that there was more than enough variation in the steering stops to account for all of the difference. His car cleared because his wheels didn't turn as far, even 1* is significant.

I would use a wheel spacer if I had any extra room between the tire and the fender before I modified the steering stops, just because you are changing the turning radius of the car. Bill Reilly probably has a bit of a biased opinion, since his RMS Alterkation suspension does increase the turning radius of these cars noticeably. I personally think that's a negative, a better turning radius is a good thing. And with a factory turn radius of 37.8' it's not like these things have a super tight turn radius. Better than say, a 1971 Mustang which had a 39.8" turning radius, but that's not saying much.

 

[JoesEdge]

Thanks for the help!

I'm going to look into the steering stops today after my kid comes back from his orientation class from the college. I may even go to home depot and make my own "wheel rite" to simulate different wheels. I saw a post here that someone used some very cleverly shaped plywood. They actually cut it quite beautifully. We'll see how it goes.

 

[JoesEdge]

So, I did some more test fitting at my local tire shop - Performance Plus Tires.

They didn't charge me a dime to test fit various wheels. Here's a few pictures of what we tried.

Here's an American Racing Torque Thrust 18"x10" wheel. The offset was way off and probably too wide too.

Seems to stick out a bit too much here.

Not enough backspacing. Too bad Amercian Racing doesn't have enough options for muscle cars that can use more backspacing. 6 to 6.5" of backspace would have been good.

This one is a Vision Model 143 18"x9.5" wheel. It fit in the back just fine, but not on the front. The front had a problem with the wheel bearing dust cap. It stuck out too far. So, these went back.

 

[JoesEdge]

We did try test fitting a bunch of Mustang wheels that just didn't work at all because the hub bore in the wheel was too shallow so even in the rear, a spacer was required. No bueno!

So....back to the Vision 142's.

In the back I have the 18"x9.5" with 6.75" backspacing.

These tires are Cooper Zeon RS3-S which was recommended by the Tire Shop. They said they're low cost and perform well.

The size was 275/40R18 for the rear.

It looks pretty close, but there's probably about 1/4" of space between the tire and the leaf spring. Actually, we were more worried about the front side of the leaf spring because the steel band that wraps the leaves together was right where the tire sidewall sits, but there's enough room there too.

 

[JoesEdge]

For the front, I went back to the 18"x8.5" Vision wheels with 6.0" of backspacing. I had worried that they would rub, but I guess seeing it with an actual tire on it is a much different thing than "guestimating".

In the front, I'm running the Cooper Zeon RS3-S 255/40R18 and there's no rubbing issues at all that I can tell at this time. I even tested to see if the wheel itself would hit the stock upper control arms, and nada! It's close, but doesn't hit. I can see why wheels with more backspacing would require tubular control arms.

Well, here's how the car sits now.

Sorry the picture was taken in a shadow. I need to take more pictures when I get some time and fairer weather.

I also got a wheel alignment done.

I set it up this way:

Castor: 3.5*
Camber: -.5*
Toe: 1/16"

It drives great! Very steady and no shaking at speed. It grips too!! I can push it harder in the turns now, but makes me realize I really need a rear sway bar.

Here's the part numbers for these wheels:

Size: 18x8.5
Part #: 142-8865GM32

Size: 18x9.5
Part #: 142-8965GM38

Wanted to give a thanks to @72bluNblu for all his help in trying to figure out whether or not these would even fit. Thanks!!