B-Body Diff, C-Body Diff, Wheels/Tires

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The discussion of B-Body differentials seems widely discussed, and an excellent option for A-Bodies looking at go to a positive offset wheel.

Has anyone gone to a C-Body differential, added Disc Brakes, and oversize positive offset wheels?

I have, or pretty much Bill at RMS will have the front suspension dialed in based on our discussion, but as I am considering wheels and tires along with the mini-tub for the rear; there is difficulty in deciding on what to do about the rear end as a component part.

Does any only how wide a C-Body diff would be with a disc kit like RMS/Bill's?

To be Continued........
 
http://sjvhk.jabzm.servertrust.com/ProductDetails.asp?ProductCode=FST-F14

This would be the wheel I think I would go with.

I saw a set on a Factory Five GTM and I love them. The Offset I feel could be tailored just enough to make everything work (RMS Front + whatever works in the rear)

I had hoped to go with a set up like this:

Front:
18 X 9 (Offset TBD)
BF Goodrich GForce T/A KDW
275/35ZR18

Rear:
18 X 12 (Offset TBD)
BF Goodrich GForce T/A KDW
335/30ZR18

Anyone have similar sizing on this type of wheel/tire/differential combination?
 
I ran a 67-70 B-body rear in my 75 Dart Sport and a 68 B-body Dana in my 71 Duster. I don't believe you will be able to get enough offset with your wheels to run a C-body rear. I would think the center of the rim would have to be almost parallel with the bead on the inside of the tire unless plan to relocate your springs inside the rear frame rails. Even on the Duster I had to at least run the 3/4" spring relocation kit to be able to run a 10" wide rim.
 
I had better clarify a few things for the build of the rear suspension.

This will be a triangulated 4-Link with mini tubs.

Hopefully this combination will afford the most possible clearance without going to a full tub. I will have from the frame rail to the lip of the quarter panel/wheel tub - 14" without rolling the lip. This in theory should allow a 13" tire without any issues.

This is all pending the appropriate backspacing.

The purpose of this thread is to understand if I am better off just buying a set of wheels that I want to use, and then cutting a C-Body diff to fit; unless I was lucky enough for the C-Body diff to just work.

I prefer not to have the deep dish look, so if this were the case, I would buy the highest offset wheel for the rear and cut a donor diff accordingly.

Sound confusing?
 
A 65-69 C-Body axle is 2.25" wider than a similar B-Body axle. You would need an extra 28mm of positive offset in the wheel to make up for that. If you can find a wheel with +50mm of offset, you might make it work to keep a 245 or 275 under the car. Figure on needing a positive 80mm of offset to keep a 335 inside the quarters.

Here's a formula for you - half the tire width minus offset time 2 plus axle width (drum to drum). That will give you a rough idea of out to out of tire width. Don't forget about converting from mm to inches. A 245 on a mustang +24mm rim on a 67 B-Body fits ok, and that would work out to 67.4559". A 335 tire and a 61.75" C-Body axle would need a +95mm offset to fit in the same envelope.
 
I need to find a B-body housing and axles.

Unless I am lucky enough to find someone local that wants to trade an A-body diff drum to drum for a B-body diff drum to drum.
 
I have a 70 B body housing and axles.Just don,t how to get it to you
 
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