Moving The Leaf Springs Inboard on a 1955 T-Bird: Anyone Done It?

I've been thinking about moving the leaf springs inboard on my 55 T-Bird for years, but I can't come up with a design that I like. Has anybody actually done it successfully and been happy with the results?

Why would you want to move them inboard? Example A:



This is what it looks like with big rubber and the springs in the stock position. You have to modify the quarter panels significantly just to accommodate the set up.

Example B:



Original car that was pro-moded for big meats and more than likely back halfed. I like the tuck-tire look.

 

I think before anyone can give you any good advice, we would need to see what you are actually working with. Pending how the back half was done my advice may not apply at all to what you have to work with. I have done it to my 57 Fairlane as well as a few other customer cars. Street version verses race version can be totally different. Get some good frame shots for us.

 

Fair enough:

 

The gold car looks so much better than the red car. Is that what you want to hear? It will save you a lot of work.

 

Nope. I just want to see if anyone else has successfully moved the springs inboard.

 

My car was modified for big rubber 50 or 60 years ago. The problem with the body work is that it's all filler attached to rust. It'll all have to be redone.

 

The answer to how to do it probably depends on how far you want to move the springs.

If you want to move the front mount to the other side of the frame, then you could just cut them off, and switch sides, and weld them to the inner side of the frame. The shackles in back could be mounted to a new crossmember that you weld between the rails. But that would go right where the gas tank is...are you keeping the original tank, or installing a fuel cell?

If you don't want to move it that much, you could open up the frame rail and put the front of the spring inside, then reinforce the sides. And build an outrigger for the shackle mount in back.

 

That's what I was thinking. I've got a kit for a 1955 Chevy that places the spring inside the frame rail. I really think that would work. I just don't have a good idea for the outrigger in the back.

I think I can fit a 275/60R15 inside the rear quarter panel just by moving the leaf inward. I'm not too impressed with the stock gas tank, so I wouldn't mind doing something else just to move the springs.

What it all comes down to is I don't want to put too much money in the stock chassis. At some point, I want to replace it with something that'll work easier with what I want to do with the car. I just want to get the car running and looking the way I want it to until I can do that.

 

The frame drawing suggests the frame itself is the limitation? The splay at the rear seems to start about right over the axle. I'm not sure how much space you'd gain moving the springs.

 

One other issue is that the frame is angled out at the back. So moving the springs will give you a little more tire room, but you might also need to modify the frame for more clearance.

edit: what he said, at the same time

 

You're both right. I would have to notch the frame where it bends to get all of the clearance I want. I have found that this is a pretty common modification on G-Body GM vehicles when you want to get fat tires on them.

 

I was looking at doing the same thing in my 57 Custom. The limiting factor is going to be the inner wheel well, at least on mine. I can gain about 2” before getting within rubbing distance on inside. Of coarse this can be dealt with if you cut out the wheel house and install tubs. Big investment for not so much gain. I’ll try and make my 275’s drag radials and suspension work more efficient.

 

I had to cut a small pie shaped piece out of the frame like you mentioned to fit the CalTracs.

 

Sorry. I never know which category to start these threads.

 

I've bought everything for this car to try to get it going. Every time I start, I hit a huge wall. The closest thing I can compare this car to is a Model A. Model A's play perfectly with other Model A parts. Introduce a new, non-Model A engine, and you have to modify everything.

This is why at some point I just want to run a totally different frame.

 

The easiest way would be to cut the frame off and back half the car if you wanted to fit 14x32 slick. Then use either a 4-link or ladder bar setup.

 

Is that picture from the 70s or 80s?

 

The bird frame is a pain to work around, especially the X member and the front one. I did a Morrison tri 4 bar with coil overs, and I’ve got 235/60 15 in back. I had a set of 10” cheaters on it at one point. But you’re right about the rear of the frame. You’ll run into that going bigger.

Also fwiw, the 56’s had a heavier rear frame (story goes first plated and then a heavier gauge) to carry the weight of the continental kit. Going big on the hp and tires may require you address that with the leafs mounted back there. I don’t know.

 

77-78.

 

Looks like you can move the front spring hanger just to the inside of the frame. You can see I did that if you look close. This is what I did for the shackle end. Works just fine. Gave me room for 10" wide rubber on an 8.5 wide wheel in a stock wheelhouse and no rubbing. I moved the spare tire well forward and reinstalled it.

 

Pist-n-Broke, YOU ARE THE MAN!!!

 

Are you wanting traction or just the look of the tucked tire?

The pic above shows how simple it would be to flip the front hangers side to side and inboard them, and to make custom rear supports to attach the rear shackle mounts. Relocate the axle spring pads and possibly shock mounts, and viola, you're tucking tire.

If you want traction, hit up Calvert Racing. They have split mono-leafs, sliders, and hangers for lots of applications as well as universal builder parts.

 

If I was going to go through the effort of moving the leaf springs inboard for racing tire clearance, I believe I would see what Calvert Racing has to offer, it may be more cost effective to install something they may have, rather then do it all again at a later date.

Moving the leaf springs inboard was a standard procedure with Mopar stuff of the 60s & 70s, there used to be a ton of info and several "kits" available for the Mopar stuff from factory engineering, and aftermarket.

With the location of the X member ends where they are, putting the front of the spring inside of, or under the frame rail might be better the moving it inside of the frame. There was a Mopar kit available at one times to do just that, and there used to be detailed instructions for doing that without the kit on line. If its still out there is any ones guess.

 

Here is what we would end up with moving the springs into the frame on Chrysler stuff. I have put several cars together using Super Stock springs which have worked good for what they were on. They all have a 20 inch front segment which makes it easier to control spring wrap up.