as anyone ever used trailer springs on the rear of a hot rod? I seen one model A with them, don"t know how they rode. It's hard to find a short spring for these short wheel base cars. I've found a 925 lb 28 in spring and a 30 in 650 lb spring, 4 in arch and 1 3/4 wide. The worst thing I see is the bushings, maybe the brass would hold up better than the nylon.
What’s short wheelbase? Why not buy Model A springs? I’m not sure what you have going on here so more details, don’t use trailer springs they are not designed for cars, use car springs.
I have no experience with trailer springs on a Model A, but even the 650# seems really harsh for a car that probably only weighs 1400# +/- on the rear axle. That would barely be 1" compression of the pair of springs. Lynn
Wonder if.........anyone ever modified a torsion bar suspension to work on the rear of a car. Worked pretty durn good on the old Plymouth/Dodge front ends! Just a thought. 6sally6
It'll be on a 32 plymouth sedan and I don't want a transverse rear spring. Was planning on coils and ladder bars, was just thinking leave springs would create more room in the car. I seen where one guy on here used F1 front leave springs on the rear of his model A sedan.
I run trailer springs on the front of my Morris Minor straight axle setup. I bought them and the mounting hardware from my local NAPA down in Florida . They had everything in stock. Different spring rates.
Try this, it worked out great : https://www.jalopyjournal.com/forum/threads/built-my-own-quarter-elliptical-springs.1115374/
A spring is a spring! Setting them up correctly is where the skill lays. Ask any vendor of trailer springs what the stiffness is [lbs/in] and be prepared for the dumb looks. Then this is usually followed up with a face saving rebuttal "trailer springs are rated differently" Trailer springs have a deep arch in them ,so they're OK[ish] for cross leafs but will cause roll steer on Rear parallel leafs [unless set up correctly] You really need to know what the sprung weight of the rear your vehicle is. On a road car the total combined spring stiffness should be 20% to 25% of the total sprung weight. Combined with a 4" to 5" spring load.[how much it compresses when loaded] So your 650 in/lb spring should have a total of 2600 lbs upon it [or it is oversprung] and the 4" arch would be near flat with this load. Wrong choice of springs is the biggest/commonest mistake in handling [yet the cheapest to remedy] Most homebuilt hotrods are oversprung nightmares.
I second the quarter elliptic suggestion. They are easy to make, easy to mount, easy to tune and you can even make them height adjustable if you wanted to. I used them at all four corners of the '27 T I built in the early nineties.
F-1 front leafs are 36" long. I'm using those on the rear of my 34 Plymouth. Model A front spring is 29"? No way I'd use trailer springs on anything but a trailer.
My brother used trailer leaf springs on the back of his Morris Minor hot rod. I think they were 27" long. Rode hard as hell but controlled the torque of a 406 SBC running 10.30s at the track.
Yeah, we took it out to see if he could get it in the USFRA 150 mph class. At 140 it would spin every time!
Pardon me for going off on a tangent on the general topic of springs, but my impression is that the subject is not well understood. As pointed out by Mimilan, a spring is a spring, the three most common types having different layout implications that must be considered in specific applications. The principal parameters of all are spring rate and maximum load, which can also be stated as maximum allowable deflection, determinable from spring rate and max load. A spring designed only to the desired spring rate can fail under highest load or max deflection (which is generally a nebulous value independent of spring design, i.e., how high is a brick lying in the road, how deep is a pot hole?). Most factory suspension designs include bump stops, to alleviate this problem. Coil springs are merely torsion bars, wound up into a helical configuration. They are chosen for packaging reasons, being very compact, and generally self-contained, mounted on shocks that must be there regardless, normally in tubular form. Coil springs provide no assistance in locating the wheels (other than vertical deflection). Torsion bars, or more specifically the required linkages/levers, can be arranged to provided to provide a portion of the wheel location task. Typical parallel leaf rear springs can provide for wheel location, but not with complete effectiveness. Under axle housing torque from acceleration or braking, springs can "wrap-up", requiring additional linkages to minimize this. To combat lateral loading defections, more links are required (Panhard rods). Also, the interleaf friction of these springs is a detriment to ride smoothness, has been addressed by various anti-friction provisions. Springs have no idea what the application is (front or rear; car, trailer, or box car), but expect to be designed for whatever loads will exist. There are many standard automobiles that have had torsion bars on the rear axle, mostly foriegn (some 50's Packards in my slipping memory are exception, and of course, tons of Indy/sprint/midget racers). The most notable example applicable here, having a traditional rear axle, is the 50's C-Type Jaguar. Others include VW Beetles, Renaults, and Panhards. The vast majority of hot rods are not prone to failure, since the springs are generally from much heavier cars. The consequence is that many rods ride like unloaded dump trucks.
There' a lot more springs than std. offerings from Northern or Tractor supply. Also need trailer mounts as leaves 1/4-3/4" narrower. Total Performance did trailer springs? on their Pro street '27. https://www.easternmarine.com/3-round-axle-steel-leaf-spring-seat-ss-300 A lot of hangers for ends. https://suspensionmaxx.com/leaf-spring-rate-calculator Ck 2 leaf 26" 500# at 300#/inch. One leaf drops to 150#/". http://rsleafspring.com/double-eye.aspx
Know any stock car people? Borrow a set of scales to see what the car weights across the rear before buying anything.
Don't count the axle assembly weight, and add for 2 or 3 inches of "bump" (selected spring rate x 2 or 3) for maximum load.
I had 175 springs on coil overs on my A sedan, aviator, and I figure this 32 plymouth will be close to the same wt in the rear. It'll have the same fuel tank and battery in the rear. I'm trying to add more room in the back of the car than what I had in the A. I figured the trailer springs were a bad idea, 650 is the lightest I can find and the 4 inch arch isn't ideal. The A rode and handled great, I'd like this one to do the same.
Don't mean to criticize here but they are leaf springs not leave springs. Sorry can't help it spelling drives me nuts. Leaves are the plural of leaf. When we talk about the spring package it is a leaf spring. When you talk about individual springs they are leaves. As in "how many leaves do I remove from this leaf spring"
I used '56 F-100 front springs on the rear of my '34. They probably aren't much different in length than trailer springs.
I helped install trailer springs on a 32 Vicky . Worked out fine not one issue . The rest of the suspension has to be designed correctly and drive it like you stole it .
Might be to stiff, I used F1 front springs on the rear of a '36 Ford PU I had, don't recall the shocks doing much work.
How many leafs did you use? I've seen some listed with 8 leafs in them. I was thinking about using 3 or so and seeing how that worked.
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