I am currently working on building a 1952 Chevy 5 window rat rod and was planning to make the front set up a spring over axle. This is my first build so it's definitely a learning experience. I bought a set of mounts, shackles, leaf spring, and upper spring frame perch. I have it sort of set up as it would be on the axle. I have the shackles set at 90 degrees from the ground so they are running parallel with the axle. Would this be the best place to have them when setting up the front axle? The other question I have is about the caster angle. When welding in the front assembly would it be best to have the spring and axle in line with each other and weld in the mount on the frame at an angle or would it be better to mount the spring and mount perpendicular to the ground and swivel the axle on the spring pivots so the axle is the only component with the caster angle? Any help is appreciated Posted using the Full Custom H.A.M.B. App!
First piece of advice is don't use the term rat rod,,,it is not well received here. Pictures would help. HRP
On the shackles, get a Speedway catalog, they have a photo in there on how to measure required spring length and how the shackles should set.
Yes, with the spring installed in the shackles they very well may be horizontal, the weight of the car, frame, motor, etc. sitting on the spring will "settle" it and the shackles end up at a 45 downward. The spring mount is where the castor angle is initially set... only small adjustments should be made using rod ends to get the castor where it needs to be once all the weight is on the front end.
thanks for the advice. We'll call it a hot rod. I mostly assembled it and mocked it up and shot a few pictures. That's the current setup I'm working with. The mount doesn't have holes to bolt to the axle yet so there is still some some room for adjustment before the holes are drilled and it's bolted to the axle.
No expert but lots of questions:- Will that spring be rated sufficiently to carry the weight of PU body. The front sheet metal, engine and radiator etc weigh quite a lot; I just stripped a 42 Chevy PU and recall how much the individual pieces weight when compared to a 'A' or similar. Spring looks like it's from a small box trailer; What are you using to attach axle to chassis, split type bones, hairpins or parallel 4-bar configuration; Whatever attaches to those plates is single sheer, not double sheer as in a batwing, are they clevices?; When setting up an 'A' with transverse spring, use single main leaf, shackles at 45 degrees as stated and set caster at 7 degrees. This should replicate loaded car at ride height; and What steering, push / pull or cross steer.
Not too sure about all the terminology but I'll try and answer the questions as best I can The spring is rated for 1,750 lbs. I plan to leave it open wheel with no fenders or hood. The engine is a Chevy 350 out of a 93 1500. The cab I want to chop and channel so I'd think the spring would be sufficient. I was planning on using a parallel 4 bar attached to the 2 holes in the mount. One above and one below the steering bar. Yes they are clevices Its the push/pull steering. The rod comes in on the left side and reaches to the front near the left hand mount. Posted using the Full Custom H.A.M.B. App!
A clevice on a 4-link, or any other non-static link, is a no-no. They have neither bearing surface, nor bushing, and will NOT tolerate movement without quickly becoming loose, and then failing.
Rat Rod fits here. No matter how hard you try, you cannot make a heavy and big 1952 Chevy Truck into a 32 Ford. Any attempt in all areas, especially the suspension will be a half assed monstrosity. Either build a early Ford or even GM hot rod, or build a proper full fendered 50s truck. The two do not mix. It was kind of a novelty in the junk shock crowd about 5 years ago but thankfully, that time has passed.
What if I were to get some heim joints and attach one on each side of the mount with a bolt running through and attach them to the bar so there would be 4 on each mount? That would give a joint for it to be able to move up and down. I haven't purchased any other parts for the front yet just what's in the picture so nothing is set in stone on what I'm going to use or anything. Posted using the Full Custom H.A.M.B. App!
My mistake on the links. They're going to be hairpin radius rods so the clevices won't be moving at all. Posted using the Full Custom H.A.M.B. App!
When did a fender less 50's anything fit here? Have you ever seen a fender less anything looking good?
The connecting 'link' between the axle and the hairpin needs to be able to flex. Hit a bump or a pot hole with one wheel and you'll visualize what the connecting joint experiences.
I have hairpins and clevis rod ends on my T and have been running it that way since 1982. As long as they are tied into batwings pinned to the axel with the spring perches you'll be fine. You guys need to lighten up and stop thinking you're all engineers...if you were, YOU'D be driving the train....lol
also have NO death wobble...WITH the tie rod out front suicide style....if you set your ackerman up and UNDERSTAND how it works, there isn't an issue.....I have gone 70+mph, hands off the wheel...straight as an arrow and smooth.
I'm sure I'll be told that ackerman has nothing to do with going straight...AND it also has nothing to do with death wobble. I just have to chuckle when guys believe their way is the only way...or the "correct" way...or the only safe way. Building cars is about finding solutions that WORK. when it does NOT work, you'll know pretty quick.
Proper Ackerman Angle is key, and you can indeed come fairly close with a suicide setup. Death wobble is more a function of a leading-link suspension setup, than it is a steering or Ackerman function. All other things being equal, you wouldn't have it with a trailing link setup. It can be induced by steering input, incorrect Ackerman, bad steering geometry, or incorrect toe (or play from worn components). It can fail to be corrected by bad shocks. It can be mitigated by a steering damper. I have an off-road truck with articulated leading radius arms on the front suspension, shallow backspacing wide wheels, and front steering. The only way I could get it to behave on the street was 1/8" toe OUT. I have been trying to effectivly 3D model and animate death wobble for a few years now. It ain't easy to convey. Everything is in play. Ackerman, caster, camber, toe, KPI, radius arm or link angle versus horizontal, radius arm or link angle versus chassis centerline, shock position and angle, and everything else. I have access to the equivalent computing power of several small nations, if I can ever get the equations right.
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