well i picked up yet another project from a local hot rod guy who had assembled lots of bits and pieces. 27 T body 31 A frame 46 in Model A rear spring ford 8 in rear 35/36 radius rods split wishbones for front original A gas tank beautiful 50s Chrysler wheels and nice tires 70s chevy 350 from a Monte Carlo TH350 trans as i start to read the the Tardel book and the threads on here I had a question: for the rear suspension I guess I have 2 options? I can use the A spring and set the mounting plates on the 8in to 49.5 inches wide (is this correct), or i've seen some people use the front spring (mine measures 31.5 wide and has 7 or 8 leafs) on the rear. this is a T body on an A frame. I am looking for a turtle deck for it as I want that style. May I ask what you all recommend for the rear suspension choice for this setup: the taller rear spring or the front spring used on the back (I have a 1in lowered spring on the front now above the axle). Thank you.
I don't think many people use Model A front springs on the rear. Later front springs are more common, 35-41. They are longer. But that's not the only consideration. With a stock A frame, the spring sits on top of the rear end. If you are wanting to use a front spring in the back, which is going to be much flatter, the spring is mounted behind the rear end. This will require the frame to be extended as the stock frame ends at the rear end. However, the 35/36 rear radius rods you have have spring mounts that will place the spring behind the rear. So, up to you, you have options. 1-A rear spring over rear, stock frame. Can use 35/36 rods but you wont need their integrated spring mount. 2-35-41 Front spring, extend frame, use 35/36 rear rods with their spring mounts. 3-Combo of those above. A rear spring, extend frame, use 35/36 rear rods with mounts. This gets ride height lower than option 1
You could just leave the model A spring where it sits in the frame and move your axle forward to have the spring behind the axle, but you do have two other things to consider. Suspension travel since the car will sit lower and the axle tube on occasions may hit the under side of the chassis Secondly, the A style spring tends to take up a lot of space in a trunk area and lose a potential flattish floor. Consider a flatter transverse spring, coil overs are pretty simple and if you want to go fancy look at a Jag diff. If you are considering decent HP be sure that your 35 radius rods are capable of doing the job...
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