On a stock A chassis (no kick up) with a '39 banjo, open drive.......possible? No happy at all with the ride of my current radius rod, modern shocks, buggy spring setup. Harsh.....is too kind a word!
if harsh is the problem changing the way the diff is located wont help, its spring rate and more likely a shock issue.
Ok, I'm pretty sure I see my issue. I did not notice this until now. I had previously changed out the main rear leaf once already for a shorter length as the first was too long. Once installed it looked good shackle angle wise but I still wasn't happy with the ride. It was better but not what I wanted so I just let it go and continued to just bang, crash down the road. Later we found a "floating" rear wood mounting block that had not been bolted down. Did that, which got rid of some of the noise but not help the ride. Now as you see, the shackle angle is very bad which to me means the replacement shorter main leaf is not short enough. Looks also like I have a leaking shock but the shock movement appears to be Ok as they are mounted in the middle of the up and down movement. I will also have to shorten the next leaf up. So, is there a formula for main leaf length...... perch c to c width/shackle "stretch" in order to get and keep the 45 degree angle? Are my perch mounts too low?
^^^^^ No just the dirt illusion of two.....only one there. Ok, so my measurements are this: perch: C to C is 47 1/2" shackles: C to C 1 1/2" My main leaf un sprung reverse spring eye C to C measurement should be ????
I understand attaching the A rear main leaf spreads 6" (3" per side) for tension leaving the shackles parallel until the body weight is applied then everything settles to the 45 degree......?????
That main leaf is "reversed eye" which is hitting the axle/mount when compressed. Reversed eye lowers the car, but is causing your problem. A stock main leaf would roll counter clockwise at the shackle, if that makes sense? Sent from my iPhone using H.A.M.B.
There is no formula for calculating the correct spring length. There are too many variables. A large spring with three curves in it, a car with who knows how much weight on it, and adding and removing various leaves. All these different things will make your car totally different than any other out there. Just eyeballing that pic makes me think an inch out of each side would be good. Take your main leaf to a spring shop and have them make the exact same shape and thickness, but two inches shorter.
^^^^^ Thanks. As mentioned....I have already replaced a spring with a narrower one but only to have it settle and still be too long. I believe I did not account for the necessary tension or stretch of the spring and once weight was applied.....so, I just keep trying having them make me leaves until one of them finally works! I think I have a plan for the right width.....see what happens.
^^^^ Yup, that I understand but I now have the right amount of leaves so I just need the right main leaf Thanks
I am about as far from an early Phord guy as you can get so bear with me, but I am a long time hot rodder and have built my share of many different suspensions and the principles don't change. That spring stanchion looks bent, but maybe that is the way it is supposed to be? Looks to me if it were straight up, the spring would clear the rear axle tube nicely and the shackle would lay out properly and allow the spring to work properly. If you need those 2 long second leaves to carry the load, that is preferable to short ones that stiffen the ride a lot more. Oh, and if a shorter main leaf is the answer you don't need to buy a new one. If you have a lot of trucking in your neighborhood, there is a spring shop to service them. They can roll a new end on that spring or even reverse the ends for a few shekels.
^^^^^ Yup. Thanks. I purchased those perches as they look. They mimic originals except they get welded to the axle housing but a little closer in than stock.
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