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['64 Cuda]

I'm putting this here because this seemed to be as good a place as any.

I've been measuring & re-measuring on my '64 Barracuda to figure out what offset would put a wheel in the center of the rear wheelwell so I could fit the widest tire. I've been doing all of my measuring on the right side because it was the easiest to get to. Today I went to check to see how close it was to the left side. The axle perches are off center on the axle by a small amount. Re-centering the axle would move it about 3/32". But the axle is off center with the body/wheelwells by a lot more. On the right side it is 2 1/16" from the back edge of the brake drum to the inner wheelwell surface. On the left side it is 2 3/4". What do I do now? Start triangulating measurements to see if the body is twisted? Forget about it & just fit what I can like it is? I was planning to offset the springs to gain a bit more room & I could center the axle between the springs when I do that. But what do I do about the other discrepancy? Ideas/opinions?

 

[AdamR]

Its common for there to be a little less room on one side then the other. I would do just as you plan. Offset the springs and center the housing. But check to make sure that doesnt put the driveshaft to close to the floor. Then I would just deal with the rest of the difference.

 

[toolmanmike]

Adam is correct! But 3/32 isn't much.That's only 3/64" per side. I would compare both sides and get a wheel that fits the tight side. The bigger side will fit for sure. I would use a wheel with a little extra room unless you want to trim the wheel lips. I've cut a lot of tires up by going a little too big.
Mike

 

[Keith Mopar]

64 Cuda, my 65 Cuda was about the same as your measurments, except I measured from out side tire to wheel lip and the difference was 5/8 of an inch. You will notice that your tires will rub on the springs before they rub on the inner fender well, so with this in mind I decided to move the springs in to get that little extra room and when I did that I centered the rearend. It is now only 1/16 difference side to side, and even to get that it took a lot of playing around. I am getting ready to order my rear wheels, so far I have come up with a wheel 9.5 wide, and a 5.5 back space, fronts will be 7 inchs wide with 5 inch back space.

 

['64 Cuda]

My big concern was the big difference side to side between the body and the axle. I went out to the shop, leveled the car, bounced the suspension around, etc. & re-checked the measurements. I feel A LOT better. Everything pretty much evened up. Any discrepancy I have now can be attributed to the axle perches being welded on the axle a little off center & the worn out spring & shackle bushings. I now have a measurement of about 6 1/2" from the mounting face of the wheel to the spring side of the wheelwell. Now I'm going to re-figure to get my required wheel offset. I really don't like using back spacing figures. I'm more interested in the offset that will center the wheel in the wheel tub. I need to get this done if I want to get Cragar SS wheels ordered before it's too late.

toolmanmike,
I was probably a bit unclear about the discrepancy on the axle. It's 3/16" off, which would move it 3/32" per side if I center it. But you're right, it's not that big of a deal. I'll still try to fix it when I offset the springs. As far as making it fit on the "tight" side, there isn't one. On one side of the car it would have been tight to the inner side of the wheel tub & on the other side would have been tight at the lip of the wheelwell.

(Edit)
I've re-figured now & it looks like I need about a 3/4" or 19mm positive offset to center the rear wheels in the wheel tub. This figures to be about equal to a 5 1/4" backspacing on an 8" wheel. I'll probably rethink this 3 or 4 times before I'm convinced, though. :scratch: