Technical Air Bags Model A Rear?

First off, this is only about the rear axle, at least for now I have no intention of changing the front. Anybody out there ever trade out the buggy spring for air bags on a Model A with Banjo rear and retaining the radius rods. My thinking would be to add a Panhard bar and put the bags on top of the radius rods in front of the axle. I would think that it might allow for both lowering the rear and improving the ride (maybe yes, maybe no). Overall it seems to be a relatively simple install (ya right, does that ever work out?). I am narrowing a Banjo axle to fit wider tires inside the fenders (pretty much like “tubbing”).Narrowing the axle will require a different spring so instead of new perches and a narrower spring maybe just as easy to go with the bags. I doubt that they could be seen from behind.

 

I didn't use bags.
A triangulated four bar with coil over shocks behind the axle.
I drove it over 100k miles that way.
Tires fill the wheel wells, no body mods.

For sure, there's not much room under the Model A.

 

That should work. Look at some small bags used as "helpers" or overloads for light trucks. I've got a pair on my DeSoto wagon for that purpose. They're about 6" diameter and are much shorter, inflated, than most. Making pads would be less of a challenge given the small space you've got to work with. As I recall, mine were intended for a mid size Chevy truck, I clamped them onto the leaf spring at the bottom, and made a simple pad on the frame rail for the top. The kit I used came with a compressor, but not tank, which would be easy to add. (Edit: On my Model A roadster I used coil-overs behind the axle from Speedway with a stainless Panhard bar. Easy to do, rides really nice. No need to reinvent the wheel...)

 

I am trying to maintain a stock appearance, no question that coil overs would do the job quite well without much effort were it not for that but you can’t really hide coil overs. Also, this is a 90% hypothetical “what if……” question so why it’s not necessary does not really apply (I should have made that clear in the beginning). I have air bags as helpers on 4 vehicles and I have had no problems with any of them and I understand the system quite well. They are used as helpers however so I am not 100% familiar with their use as the only spring. A friend of mine put coil overs on his A and the ride was terrible but his system may have been flawed. I’m thinking that if the bag was on top of the radius rod and in front of the axle there would be a “leverage affect” that might make for a better ride and it could be adjusted to match the load (mine is an RPU so there is always the possibility I might carry more load). But like I said, 90% hypothetical.

 

I know how to make coil overs work, because I know valving and how to get the springs right.... but I don't know how to make them look good...

I would look into Sumo's over the airbag deal.....

 

Why keep the banjo axle?

 

How about a picture of this 28 RPU ?

 

Does seem to be going through a lot if hyperthetical iterations recently.

 

I'm not seeing the radius rods being capable of taking the weight of the vehicle.

Chris

 

Here are probably the only airbags we be talkin' bout here

 

If a bag or hose were to fail, that would create a problem, similar to what happens if a coilover bolt/bracket breaks.
It can happen if the rod is actually driven.

 

I had surgery and can’t do a whole lot at the moment except dream and plan. I want to keep the Banjo because as my first sentence in post 4 says, I would like to keep a stock appearance. One of the points I tried to make about bags is that they would be hidden, the coil overs, not so much. Thanks for the comments Brian.

 

Bags are for vacuum cleaners.

 

Isn’t the whole idea of a hot rod or custom to make something you want because you want to do it? Isn’t that what the term “custom” means? Just because it’s never been done (to your knowledge) does that mean that it can’t be done? Some comments as to how it might be made to work is the whole idea of this post. Yes, I have asked a lot of questions and dreamed up some things but so what? If you don’t wish to participate than don’t, I won’t be offended.

 

PS; I had no plans to alter the rear suspension at all. I had no plans for it and I did not know that I was going to need to. I have already explained several times how it is that the problem came up in the first place. I am simply trying to explore what options I might have. I am trying to best play the hand I was dealt, that’s all.

 

If you want to keep it looking "traditional" you are gonna want to keep a transverse spring on the banjo rear. Now, if you want to make that adjustable, you will have to figure out a way to use an air bag(s) to raise & lower the spring mount, or the rear frame section. I can think of a few ways to do that, but it seems like you would lose a bunch of room in the back - as in no back seat.

 

I did a FF deuce pickup over 20 years ago that I bagged front and rear. I mounted the convoluted front bags on top of the 32 bones right behind the wishbone yoke. I kept the cross leaf spring for a locator but with only 3 leafs. On the rear I put the bags over the axle and kept the cross leaf also with 3 leafs. 32 bones on the front with panard and ladder bars on the rear with long panard. Just ran a pump with small tank under the box with the dual gauge controls under the seat. Worked great, rode great. I had about 3 inches of drop from driving height.

 

Thanks Gary!

 

Gary, I’m ***uming

 

Any photos of the ch***is? That sounds like a n interesting setup