On a 29 ford chassis with a straight axle with the spring attached to the front frame boxed crossmember. the spring shackles allow the front axle to move side to side when i steer.. if i get the car sideways i am getting an unstable front end feel( like bump steer) and the the car is numb. the shackles are allowing the axle to move away from square Is there a solution to this? it will do the same thing in a long sweeping turn like on/off ramps.. it wanders.. is it practical to do a stabilizer bar from chassis to axle.? is that viable.?
i posted the wrong video.. i have a video of the chassis moving parked.. ill find the link and post it. but this video is the car ^^ so it shows what car i am talking about.
so a pan hard bar on the axle is an acceptable solution? Ahh.. i see them avail.. thanks wasnt sure what search word to use for this application. thanks.
the axle sets at the front of the frame/cross member. the wishbones are parallel with the frame. so i was thinking of making a bar/brace/pivot. from the front frame over to the upper leg of the shackle . the arc should be parallel so it should move free and not make any bump steer. i dont see any room to mount a prefabricated/store bought drag link/panhard bar. or any room.. i have some pictures.. i was thinking of making a bracket on the frame. a bracket fabricated to straddle the upper shackle and mount to that. then put a bar connecting the two with a small "dog bone"that allows both ends to pivot. it would be a short length dog bone.. but i am trying to see if mounting one on both sides would do what i need. ill add pictures.
Do you have any decent photos of the front suspension? It might be something as simple as the shackles being too long allowing things to swing on them a bit. We used to see that on long shackles to lower fat fender Fords years ago. They turned a pretty decent suspension into a swing set as far as the body not swaying went.
The dead perch on my roadster is from The Deuce Factory but no longer being made as far as I know. As Marty will attest to I'm sure; many have been built from scratch, the old dirt track racers used them regularly also.
i am waiting for pictures to down load. this isnt the best pic.. but if you look at the upper shackle mount (its attached to the wishbone) and the front corner of the frame . that is where i want to build a link bar to connect these two parts
Can't see your idea working too well to be honest. The short length will give quite significant changes as it moves through its arc, although admittedly this will be reduced by short suspension travel. Doing it to both sides would tend to lock it up or quickly find the weakest point and then ruin your day. Some folks have done variations on fork type arrangements with a bearing sliding up it. All mounted in the center of the frame and axle. See Doane Spencer roadster. Chris
A pan hard bar should go from the frame rail that the steering box mounts to, to the opposite side wishbone as close to the axle as possible. Like below. stole this from The Belly Button Bucket thread here on the HAMB. https://www.jalopyjournal.com/forum/threads/the-belly-button-bucket-build-thread.1000590/
ive been looking at what i have.. and the pan hard bar that crosses center would be nice.. i am having a hard time figuring how to make one work. the spring sits under the nose of the frame.. so its in the way to put a bar in that location. it would have to run where the spring is currently occupied. and i have to mount to the axle. the best place is the upper shackle.. but again that is inline with where the spring is located. the axle sits out in front of the spring.. if i mount a bracket on the frame to reach forward to get inline with the axle.. then the steering will strike it when the suspension moves up and down. i am trying to look where to put it..
i dont see a dead perch working as the axle sits out in front of the spring.. getting a pan hard bar from one side of the frame to the other is gonna be hard.. the wishbones are level.(actually above) the frame.. the panhard would strike the frame.
i realize the arc of the pan hard needs to be great so as not to push or pull the axle away from center as the suspension moves... but i am limited on space and interference. i am going to have to think more on how to make this work.
Your not the only one too just look at another hot rod an think,That's what they did ,it's what I'll do. Fact is too many do that,an what they saw was poor/bad engineering an bites them later ! Shackles done right,are designed to be ,when fully loaded at 45*=this holds axle on center vs if they hang lower,just swing back n fourth letting axle go out of center to frame. Fix is too make one side only a deadperch or add a pandhardbar/////////DO NOT ADDED TOO BOTHSIDES,one side only,or shorter spring or wider mounts. Another big misstake often made from doing the same thing you saw,is with steeringbox mounting an adjustmints; Box MUST be set on the boxs center,not ever adjusted off its own center of travel. Also don't do cowel steering{90%+ times it's done very wrong,an if that makes you even ask why-you will do it wrong..........100%
Another thing I notice is that on your pictures one of the spring leaves looks loose or possibly broken. Are the "U" bolts tight? What shape are your shackles and bushing in. Along with a Panhard Bar you might want to replace the bushings. I would jack up the front end and take the load off it and see what is loose and correct it. Don't over engineer your front end, Nailhead gives you a great example of how you can correct your issue.
does the pan hard bar have to remain perfectly parallel with the axle? i am looking at geometry.. but if i can allow the panhard to run at some what of an angle if chassis mount sits behind the axle mount.. that would put the rod at a slight angle/ off parallel to the axle. iam working this out.. It will try to pull the axle fore and aft.. but i dont have that much travel.. and if i dont have that much angle..? Ill tell you i keep forgetting to put a zip tie on the shock strut.. and drive it on a normal situation.. and then look at the zip tie to measure suspension compression.. i can calculate real or actual travel on this set up.. but i am guessing 5-6" max .. 3"up-3" down.. but its a guess right now. body roll (with transverse spring) is creating a fair amount of my condition..as much as the travel is. i know this is what it needs to fix it..
woodie.. good eye..im gonna look at that as soon as i finish my dinner.. i had to look at my own pic close ..to notice, tht might be why the cars acting up
Your shackles appear to be angled too low. There are ways to control this situation, but the best is to have it right. With what you have and since you are running cross steering which will also influence what you are feeling. Take a look at this thread and see if you can glean something from it for your situation. https://www.jalopyjournal.com/forum/threads/tranverse-springs-tech-info.1112840/
thanks for the link fiftyv8.. i am reading... i am also newly thinking my springs have lost some arch and this is why the shackle angle is off. there is zero preload. when i disassembled the shackles.. also i disassembled the front leaf and its not cracked or failed.. i suppose the 2nd spring leaf was just cocked a little.. but it appeared to be undamaged.. fwiw..
My model A has no front shocks leafs removed and used as spacers SBC with automnatic and never moved around once I tighten the hairpin mounts,it had a stock frame then.
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