15x8 w/ 4.5” BS on front/good handling size?

[67autocross]

The slot mags are crazy light… the 10 inch rears are probably 20lbs…I would guess you could knock 60lbs off the car on a 15x7 front and 15x10 rear wheel combo over steel…

 

[67autocross]

A 225/60/15 on a cop wheel ( 4.25 backspace) is getting to the limit especially on the duster/valiant fender… a 4.5 or a little more backspace 15x7 would be likely better as per Abody Joe….

 

[abodyjoe]

i had my 15x7 steel wheels made with the custom backspace (4.5")by wheel vintiques. their standard wheel is 4.25 backspace.

 

[go-fish]

15x7 (4.25 bs) 225/60-15, 1.03" bars. The tires will pull back the fender trim at the top center in a hard corner. I moved the front fender out a little with the fender support rod.

4.5 bs would be great. What tire would you run if you went to 15x8 (4.75? bs)?

 

[67autocross]

15x7 (4.25 bs) 225/60-15, 1.03" bars. The tires will pull back the fender trim at the top center in a hard corner. I moved the front fender out a little with the fender support rod.

4.5 bs would be great. What tire would you run if you went to 15x8 (4.75? bs)?

View attachment 1716272133View attachment 1716272134View attachment 1716272135

i had my 15x7 steel wheels made with the custom backspace (4.5")by wheel vintiques. their standard wheel is 4.25 backspace.

 

[autoxcuda]

15x7 (4.25 bs) 225/60-15, 1.03" bars. The tires will pull back the fender trim at the top center in a hard corner. I moved the front fender out a little with the fender support rod.

4.5 bs would be great. What tire would you run if you went to 15x8 (4.75? bs)?

View attachment 1716272133View attachment 1716272135

I would just stay with custom 15x7 rim with 4.75” bksp. And a 225/60/15 tire. But need aftermarket upper control arm. And need check rim lip thickness/design.

Otherwise the next tire is a 275/50/15 Nitto Drag Radial. That I hear is a better handling tire than BFG/Cooper stuff. For that wide a tire up front you will need to start rolling fenders, really pushing our fender braces, cutting/bending back front lower fender lip, etc, etc. You could run a 15x8 with that tire.

 

[autoxcuda]

On the factory front end, 3.75 bs is about all you can use, before the wheels get into the upper bjs with 15s....... and/or the rubber gets into either the strutrods, the frame-rails or the fenders.
BUT IMO,
almost worse is that as the center of the wheel moves outboard of the design centerline, this creates a scrub radius that tends to manifest as wandering in a straightline, which for a streeter is the death-knell of long-distance cruising. Even a half-inch is annoying by 40mph or so. Which is why I went back to a 7.5" wheel, and a factory-height tire.
but, the backspace of 3.75 on a 7.5 wheel, (which is 8.5 from outside to outside) pushes the wheel centerline about a half inch to the outboard of the design centerline, and so, my car does wander some, on the hiway. To combat that, I pump up to pressure to 32, from the usual 28psi, in the 235/60-14s.

BTW
I love those lightweight slotmags, and have accumulated several sets of various offsets and widths. and,
They are easy to repair after I curb them ...........
and I seem to have curbed a few.
Those slotmags are about half the weight of a similar-sized steel wheel; and, in town, that makes quite a difference when bouncing thru potholes and hitting speed-bumps.
I get quite a kick when launching over speed bumps at speed, while watching some joker crab-walk his lowered tuner-car over same bump. I give him a lil burp on the throttle as I leapfrog the bump, for a dual 3" canons wake-up call, lol.
But I digress.

Nice-looking car. I had one like that in 1970, except PantherPink/or whatever Dodge called it..... Worst handling car I ever owned ........... but it sure was fun learning to drive it.

I’ve run 15x8 steel rallyes with 4.5 backspace. With 73-76 Disk conversion and stock Upper Control Arms. And with 12” police rotors and pin calipers.

So a 15x7 with 4.5 backspace will also work

On my Barracuda and my Dart

 

[AJ/FormS]

Yeah, I did say on the factory front end .............. and I don't see OP setting up his "cruiser" like yours.
However;
I applaud you for making it work, cuz;
I made it work on the factory 68 to 72 front end, with the KH 4pots, at 4.25 bs; and I know how much work that was.

 

[67autocross]

I’ve run 15x8 steel rallyes with 4.5 backspace. With 73-76 Disk conversion and stock Upper Control Arms. And with 12” police rotors and pin calipers.

So a 15x7 with 4.5 backspace will also work

On my Barracuda and my Dart

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I’m on the hunt for a 15x8.5 center line auto drag wheel with 4 3/4 back space to try…after my 7.5 inch slot mag fail…

 

[autoxcuda]

I’m on the hunt for a 15x8.5 center line auto drag wheel with 4 3/4 back space to try…after my 7.5 inch slot mag fail…

What brake setup are you using?

 

[4mulas]

I’m on the hunt for a 15x8.5 center line auto drag wheel with 4 3/4 back space to try…after my 7.5 inch slot mag fail…

You’ll be hunting forever. They didn’t make one. 4 7/8 back space was the most on an 8.5 Centerline. These will have your tire within a millimeter or two of touching the springs..

It’s the tire bulge or section width that you need to worry about.

 

[autoxcuda]

You’ll be hunting forever. They didn’t make one. 4 7/8 back space was the most on an 8.5 Centerline. These will have your tire within a millimeter or two of touching the springs..

It’s the tire bulge or section width that you need to worry about.

With 15x8 rims with 4.5 backspacing at 245/50/15 tires I had no touching to leaf springs or inner wheel well. It was close though. That's "stock" small bolt A-body rear width with stock axle flanges and drum brakes (just re-drilled bolt pattern). OE Leaf springs 100% stock location. That’s the inside clearance.

67-69 barracuda have more outside clearance than 67-69 Darts. So that’s not comparable.

The low profile tires without much budge or flex help a ton.

 

[4mulas]

With 15x8 rims with 4.5 backspacing at 245/50/15 tires I had no touching to leaf springs or inner wheel well. It was close though. That's "stock" small bolt A-body rear width with stock axle flanges and drum brakes (just re-drilled bolt pattern). OE Leaf springs 100% stock location. That’s the inside clearance.

67-69 barracuda have more outside clearance than 67-69 Darts. So that’s not comparable.

The low profile tires without much budge or flex help a ton.

Sure. But he was taking about, and my comment is about centerlines

 

[autoxcuda]

Sure. But he was taking about, and my comment is about centerlines

Aftermarket large bolt axles push out 1/4” per side wider than a stock A-body 8 3/4.

If you a have lower profile tire with not much bulge, a 4 7/8” backspacing rim might work with some thin spacers. It’s easier to adjust outwards then inwards.

Would need a particular tire for sure.

 

[4mulas]

Aftermarket large bolt axles push out 1/4” per side wider than a stock A-body 8 3/4.

If you a have lower profile tire with not much bulge, a 4 7/8” backspacing rim might work with some thin spacers. It’s easier to adjust outwards then inwards.

Would need a particular tire for sure.

It ‘might’.
But on my 70 duster right now with 5x4 and that backspacing it would be maybe 1/16" away from the spring, if not touching. So I guess a LBP conversion might achieve a 3/16" gap between the spring and tire. All this on a 28x10.5. Right now I run 27 x10.2 on a 4.25 bs (sbp) and i have about 5/8" gap to the spring..
Regardless, it’s close a would likely rub under tire flex

 

[autoxcuda]

It ‘might’.
But on my 70 duster right now with 5x4 and that backspacing it would be maybe 1/16" away from the spring, if not touching. So I guess a LBP conversion might achieve a 3/16" gap between the spring and tire. All this on a 28x10.5. Right now I run 27 x10.2 on a 4.25 bs (sbp) and i have about 5/8" gap to the spring..
Regardless, it’s close a would likely rub under tire flex

Yes.

Those are high aspect ratio drag tires with big sidewall bulge and lots of flex. You’ll need to get that rim edge away from that leaf.