Can anybody tell me where I can find rear radius rods that look like this?: I found this picture on google but I couldn't find them for sale. Sent from my iPad using The H.A.M.B. mobile app
Well they are fabricated from rectangular tubing that someone tapered the end and welded in a bung. Something one of several Hamb fabricators could knock out. That little Logo down in the corner looks real familiar but I can't remember who it belongs to.
school me on this. that style was used on most of the drag cars in the mid 60's. or are you saying for street? i could understand that. the ridged ones would lift the body and squat the rear down.
Do you drive on a drag strip? Bars like this, attached to a nice, rigid axle housing, turn the axle into a giant immovable anti-sway bar, disallowing any suspension movement but directly up and down, on both sides. Couple this setup with conventional front suspension, and you are headed for a handling and cornering nightmare. Even for a drag-only car, they would be way too short.
Here's an alternative. Trailing arms off a '99 Land Rover Discovery. Stout with rubber bushings. Made some brackets and mounted them to an 8" rear. They look good and work quite nicely. Best part is the price. $33 for the pair at Pick-N-Pull!
Thanks for the input guys. After doing a bunch of searches I realized that these things are probably bad news. But while we are on the subject can I ask you another question? I see all kinds of bad things about split rear bones and similar set ups, yet why do so may kit T-Buckets seem to have rear hairpins? Isn't that basically all the same? And would swiveling rear leaf spring perches help to flex more in this type of set up? Sent from my iPad using The H.A.M.B. mobile app
i don't really get the rear twist idea. a sold rear isn't supposed to twist. it's movement is only up and down. if it twist it would really cause a dangerous rear sway to it. the only thing i see, would be a change in the pinon angle, but that's what u joints are for. like i said in my other post, street or drag?
On top of that think about one rear wheel going up over a bump while the other side wheel has to stay on the pavement. The rear suspension has to have some side to side articulation in order to work properly. A huge sway bar won’t let that happen.
Hairpins and split bones both twist. Not the same thing. You cannot use these control arms with parallel leaf springs, unless you have housing floaters, which allow the leaf springs and the arms to operate in different arcs, and again, drag race only.
The axle housing does not twist, the control arms do. If they do not, you have bind. If the control arms are rigid, and solidly connected to the solid rear axle housing, you have turned the entire rear suspension setup into a giant anti sway bar. This can result in dangerous over-steer, when the body rolls on the front suspension. Every bump wold lift BOTH sides of the rear suspension, causing the rear of the car to hop, potentially leading to, if in a corner, catastrophic loss of control of the vehicle. Roll in the front suspension will cause the body to take the rear axle with it, lifting the inside rear tire in a corner, shifting 100% of the rear load to the outside tire, likely exceeding its ability to grip. Dropping a rear tire into a pot hole, even going straight, will cause roll in the front suspension, possibly inducing bump steer, or possibly even unseating a front wheel. All properly set up solid rear (and front, for that matter) suspension MUST have allowance for lateral articulation. It absolutely cannot be limited to just up, and down.
i get the street thing but i am a drag racer and they work fine for that. they push the body up and plant the tires. since the site is more about street than drag i will shut up now.
Guess I type slow, Gimpy's faster. . stinky; Those aren't radius rods. At least not in the usually accepted vernacular of hotrodding or streetrodding. There is some flex/twist in the radius rods, & 'bones. There shouldn't be. The reason a lot of folks get away w/stuff like that, is because the frames do flex/twist/etc, so destructive forces aren't concentrated in one place all the time all at once. Usually. Still, not a good idea. & also at least one of the reason(s) why a lot of cars don't handle well. Gary; I do believe & it's my opinion,that the OP 1st post pic, is a really bad/poor/lack-of-understanding/copy of the HotRodstoHell converging trailing 2-link "truck arm" suspension. Which is its' self a copy of the NASCAR rear suspension, which is a copy of the GM(GMC iirc) 1/2 n 3/4 T truck rear suspension. It does work rather well if you have the room for it, & if it's put in correctly( GMs' design geometry followed), which includes the proper trailing arm design(2 'C' channels riveted back-to-back, allowing twist along their length, but ridgidity in the up/down movement), bushings in the front(for twist n some shock absorbing)(or a *very large* heim joint/'johnny-joint'). Done correctly, either street, strip, round track, limited off-road, will all work w/this setup, both in terms of flex for road irregularities & tire planting. Pete-n-Jakes rearend setup is based on this, just uses thin tubing in a radius-rod format/look, but the design results are the same, although theirs looks 100x better than the GM version, & is probably 1/2-1/3 lighter. You're correct, the rearend shouldn't twist, but the suspension has to move in 3 dimensions to work w/o binding. & of course, for suspension to really work well, the frame should have no twist/flex in it. The engineered twist in the trailing arm isn't a problem. Properly installed, if you removed the shocks n springs for testing/demonstration purposes, you could probably get 18"+ lift on one outside end of a rearend, w/the frame staying flat on jack stands, just using your hands. It's amazing, really. Remember, in addition to the whole rearend moving up n down, each side also moves up n down seperately. Limited of course to each wheel being tied to the other one via the solid axle. Even on a drag-only rig, if it has suspension, I believe it'd work better if the suspension can work properly, instead of bound up. For a visual, think of a pyramid almost laid on its' side, so the base(represents the rearend) is 90* to the table & the tip is held by your fingertip. Think of the outside edges as the wheels & the tip as the converging point. Hold the tip still, & rock the edges in an arc clockwise n counterclockwise while simultaneously moving the base up n down. Rearend can n does the same movements. The steel tubing shown in 1st pic won't twist, but the ends, or something else, will eventually break, unless there is only up/down movement, like on a drag strip, n the car/truck never gets sideways. Then the bars n rearend = a very large anti-roll bar of unknown stiffness. BTW; how's the smokin'(!) VolkRod doing? Haven't heard/seen anything about it lately. Hope it's put a permanent grin on your face... . Marcus...
Haha! a very good example of very stiff rear "roll stiffness" FWD cars are set up this way to keep the front wheels planted for mid corner and corner exit traction. In the early days [pre slipper diffs] they use to set up the front really stiff and rear soft.[opposite to FWD] Cars like Lotus Cortinas would lift the front wheel on mid corner to corner exit
Just a question for you experienced guys... is it possible to run a parallel four bar with a stock model A spring? Or at that point do I just have to go with coil overs? Sent from my iPad using The H.A.M.B. mobile app
Yes. Four bars are fine with a transverse leaf. Model A's don't have enough travel to get too far into bind.
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