Moving leaf springs inboard

This is for E-body...

When you move the springs into the frame rails and use offset rear hangers,
what is the new spring perch distance ? Center - to - center.

Factory E-body is 46".

I don't understand why you would need offset rear hangers when you move the springs into the rails. I would think the easy and better way would be to use sliders instead of shackles.

Gus

I used a pre '71 B body housing. Fit fine and was cheap. On my Cuda, to take full advantage of the wheel well opening, I had custom back spaced wheels made. 10" rims with 275 or 295 tires fit fine.

I was looking at the US Car Tool mini tub kit, this moves the springs into the rails.

http://store.uscartool.com/70-74-MOPAR-E-Body-Mini-Tub-and-Spring-Relocation-Combo-Kit_p_153.html

Agreed, plus if you use the rear offset , which moves the springs to the SIDE , how are you going to move it to the side in the front ?

The offset is for people that don't want to cut the car I believe .

My Challenger is mini tubbed, springs moved inboard with Caltracs and split mono leafs. Also squared the springs parallel to each other. My rear hangers are mounted to brackets on a chromoly tubular bar from frame rail to frame rail from the front. The bar serves three purposes. Ties the shackles as mentioned, my down bars in the trunk tie into this bar from the top through the trunk pan, and my parachute mount ties into it from the rear.

That's a lot of money for those parts
it is not hard to have the front piece made by a local shop and buy the spring perches and make the rest of the parts yourself

f you move the spring in 3" per side using the frame rail kit, the new perch center to center would be 40".

If you move the front eye into the rails, there is a corresponding rear rail offset rail that allows the shackle to be the regular vertical kind. There is not a 3" offset shackle that allows the front eye to move into the frame rail while retaining the original shackle mounting point. If you look closely at the rear view in the linked USCT site, you will see this rear frame alteration.

If you use the bolt in, 1" offset front hangers, which do not cut into the frame rail, you must also use the 1" offset shackle kit.

Keep in mind that the rear frame rails in an E body are splayed wider at the rear. You can only move the wheel tub in about an inch, maybe 2, before you will now have frame rail interference, regardless of where your springs are located

TC, curious have you done this operation on your E-body ?

When moving the spring that much, do you get into the rear valance with the shackle? I just used the good Dr's offset and had to 'massage' the relief in the rear pan for clearance.

I evaluated both the 3" and 1" relocation. I elected to go 1". This is because it got the spring out of the way without needing to modify the wheel well or the frame rail. With this I change I have a 10" wheel with a 12"/305 metric tire and plenty of room everywhere. I have mocked up a 13.5"/335 metric tire that appears it would fit with a wheel with exact backspacing.

If you look at the stock wheel well, there is around a 1-2" space between the rear edge of the well and the frame. If max tire size is the goal, splitting the well and installing the spacing strip, the USCT kit has this piece, would gain you that last 2 inches. In this case, a 15"/365 metric wide tire may be able to squeeze in there.

Beyond that, you have to modify the frame rail.

Don't forget we have a lot of the Direct Connection info along with some other members feedback in the Tech Section: http://www.moparts.org/Tech/Archive/rearsusp.html Look at the Rear Suspension Info, Spring Relocation (rear), and How to fit BIG tires on a Cuda.

Mine is moved in 3". It does not get into the rear valence. Here is a rear shot of my car done.

Cuda vs Challenger maybe? Rear valances are very different in that area.

A Cuda may be different.

I had to trim the valance braces on my Challenger, this was only the 1" Dr relocation kit.
I think he now has a note about this, not needed if you don't have the cutout valance.