A 32 Plymouth would have left the factory with parallel leaf springs, and they would have been 1 3/4" wide, but your not limited to using the original springs, or off the shelf trailer springs. The correct way to start would be to weigh the rear end of the car, and then measure to see what length spring (measure the length from the front mount to the center bolt, known as the front segment. Then measure the length from the center point to the rear mounting point, known as the rear segment) that will locate the rear axle where you want it under your car. There are several places that can be found that specialize in leaf springs (Google is your friend). Armed with the rear weight, and the length of each segment for the total length of the spring desired, you should be able to get a set of springs that will work very well for you. Gene
i figure i will weigh in on this too. i am in the process of building a '53 chevy 3100 truck. it will be just the cab (which i took 13 inches out of the center and cut off the top/roadster) and a 4 ft long box with a sbc/t350. i am using the og frame with the back 4ft made from 2x4 steel. i am using the front springs for the back. i figure i will eventually remove a few leafs when i get it running though. to be continued.
This procedure gets the axle located dimensionally, but does not address spring constant, which is the most important parameter (along with load capacity) in ride and roll resistance (cornering).
If you take the vehicle rear weight, and the spring lengths to a real leaf spring shop or website, I'm pretty sure you will get a set of springs that will work. One of the expected questions the spring shop will ask is what the vehicle will be used for. If you can't get the right springs with the info provided, you probably should get a better spring shop. Maybe I've been pretty lucky with the dozen or so sets of springs I've bought through my local spring shop. Gene
I found a coil spring kit, 175 LBS, at Speedway. It's $119 with the buckets and all and looks like it would work out good and you wouldn't be able to see them hanging down like a sore thumb plus they look compact. Every coil spring I've looked at cost more than that for a pair. Coil overs would be simple but I don't really like the looks of them.
I almost did a truck arm/coil setup on mine. But having never done that before, I wasn't sure how that would work out. Sure looks simple...
chester greenhalgh, in his "t-bucket roadster" book suggests using springs for a trailer. you'll have to discard some leaves, but he used springs that were within 3-4" of the hangers.
Most people do not deal with this on a regular basis. (There are obviously some here that have dealt with it a lot). Having very little experience what I would do is go to a good spring shop. I was at a well respected shop and he showed my all the metal stock they had. Never again will I re-arch springs myself with it being so easy for a place like this to do. It must have taken him 10 minutes to do what it took me close to two days. He said to just let him know the length of the perches. The weight and what kind of application it was for. They would have a set made in short time. I don't recall the price he quoted me but I was surprised it wasn't more.
I became fascinated with leaf springs at an early age on the ranch. We would “ beef” up our trucks by adding leaves to the springs. There’s a lot more to leaf springs than first meets the eye. They are “ tuneable” by shortening and adding or subtracting leaves. Ford in the seventies ,on OT pick up trucks , had the best system I ever saw with four sets of progressive overloads on their rear springs. Made the trucks ride good empty or loaded and would haul a tremendous load. I had 4400 lbs on a 1/2 ton one time, hauling a load from Muskogee to Joplin, Mo. Thats two and a quarter tons on a 1/2 ton truck! Not sure if this info would be much help on a hot rod. But maybe some of it can be applied? Bones
Mike: I use trailer springs under the rear of my Model A Coupe now for 30 years. Mine are the 1-3/4" wide, lightest 2 spring unit you can find on the net for like $18.00 each. I only use the main leaf on my car. Here is where I bought mine: https://www.easternmarine.com/double-eye-trailer-leaf-spring-una-144 I built custom ladder bars so I mount the spring with shackles on both ends of the spring which makes it a floater so you have no binding at all. I have made 4 sets of different length eye-to-eye shackles to adjust ride height. Works like a charm for me, my Coupe weighs in at 2010#, and I have never wore out the nylon bushings and I have put a total of 70,000 miles on this design over 30 years.
Glenn........that's a new one on me. Shackles on both ends. Not sure why unless it's to control wheel hop. Do the bushings in the ladder bars wear?
It acts like a floater set up and the ladder bars prevent front to rear movement. I've never seen it but it's a pretty dang good idea!
Rocky ole-pal .... a ladder bar car must have the axle 'float' and this is a poor-mans floater. The shackles keep the rear end side-to-side movement from happening as does a watts link does. The shackles on both ends allow the suspension to articulate with no bind, as the ladder bars are anchored to the chassis and housing. I named it my: "semi-elliptical floating 2-link" ... rear suspension. These are the things that one can do when not building a car out of a magazine or parts catalog. I dreamed this up over 40 years ago and built several on them. Remember, your brother Scotty saw my Coupe with this suspension at the Good guys in Des Moines Iowa in 1993 and flipped out on how simple it was, as then went home and built his Morris Minor with it.
It works brother ! I learned how to build cars around some pretty dog-gone-smart ole-boys back in Sodville Iowa as a kid. These guys built circle track modifieds, stock cars, drag cars and hot rods, and they just flat figured things out. We either found something in a junkyard that could be used or modified, or off a piece of farm equipment, or we just made something with our hands. Todays market world has ruined creative-low-buck- ingenuity, in my opinion. Heck, I've been running a dead-perch on my cross spring front suspensions for 40 years and guys tell me "that can't work" !!!
I've probably used 10 of them coil spring suspension kits, hard to beat the price or the ride. I also get my triangulated 4 bar kits from a company called airbagit.com, around $150 shipped.
A key component to this rear suspension is 'shock location' WITH adjustability . When fabricating, I set it up with my different ride-height set-ups, and fabricate upper shock mounts that allow the shock to sit from straight-up 90-degrees (vertical ) to 80- degress to 70 - degrees, and also make them at 2 different height-holes so when you raise or lower the suspension, I can keep the shock travel where it should be. One thing I want to point out regarding shocks: On my latest version of my Coupe (in avatar) I used Monroe Corvette Gas Charged Shocks for the first time, and as of right now, I'm on the fence on going back to the Monroe old-style oil filled style. In my opinion, the gas charged style is to "harsh" for this light-weight of a car. The oil filled units rode much better. You can see the upper shock mounts in this picture. Glenn
I always made my own 4 links with DOM tubing. Ahotrod do you have a pic of your dead perch front suspension? I'm like you, I try to make everything I can. When I started drag racing with very little money if I didn't know how to do something I taught myself. Still don't have much money.
98% of traditional rod suspensions that I've seen have leaf springs with shackles on both ends! Everything with pre-1949 Ford style suspension. On the springs discussed here, the axle is attached at the center, whereas with the "buggy" spring, it's the chassis attached at the mid-point. Ford angled the shackles substantially, to provided some lateral stability, which is of no help if a Panhard rod or similarly functioning linkage arrangement is used. Ford did provide Panhard rods in the final model year for this susension.
I saw this really cool '32 sedan at B-ville that convinced me to use short parallel leaf springs on the rear of my sedan. I will also run a torque arm to control axle twist. <<<My coupe also has parallel leafs...
Forgot to comment on the shocks, I think the gas shocks don't work well on a light car in the rear. Just my opinion for what it's worth, what kind of shock did you use on yours? I know you said the gas were corvettes. I found the old mopars had a really nice short shock for the front, I was going to check Rock Auto for a set of rears off of a old dodge or plymouth. I like something that slips over a stud on each end. Easy to make mounts.
Mike: I've searched Gabriel, Monroe, KYB and found no regular old style hydraulic shocks in there product line up anymore. It appears as all are Gas Charged units now, bummer. Glenn
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