Here are pictures of AV8 drive line. Trying to set up Pinion angle. See thread 3/13/18 for particulars. I need to come up with 2 degrees up at the pinion end but not sure how to accomplish that. One suggestion was to pie cut the radius rods from the bottom I would think. That would make the rear end point up.
OK on your last thread I was not aware that you were running open drive. Sorry for the bad advice. You have two options, and maybe you will have to use both of them. You can shim your spring to change the angle of the spring ( this will keep it from binding) and you can slice and weld your radius rods ( like you do on the fronts) to set your angle. You are way overthinking it, your pinion is perpendicular to the front face of the pinion support, your tail shaft is perpendicular to the rear face of the tail shaft housing. Find a flat place to measure your angle and make the two faces match in angle or make the pinion angle equal to the tail shaft angle. Done deal.
I agree. We are often guilty of over thinking. When we were young we wouldn't have given pinion angle a second thought. A couple things, universal joint angle become more critical the faster the shaft is rotated. On a parallel leaf spring rear end pinion angle changes all the time, during braking and acceleration. No one notices, and we never think about it. 2 degrees is nothing. Put your roadster together, go for a ride, and let the u joints do their job. You'll be fine.
Having the bone pivot forward of the trans u-joint center line? Porkbeaner speaks of cutting radius rods. A cut is a cut no matter what it's for. Why not shorten the rods so the u-joint CL and the bone pivot CL line up vertically? Would that not allow the rear to go up at the nose then (?) since now the pivot can be raised because now there will plenty of room to do so.
Why don't you just cut the 4 tack welds that hold your radius rods to the rear end and rotate your rear end up to the correct angle? You can then shim or cut the top of the rear cross member at the top where the spring attaches to match the angle and re weld assuming the spring is in a bind. At least they look like tack welds but are hard to make out. You do understand that you need to set the pinion angle at your final ride height. Are those copper brake lines?
It's going to be hard to drill threw the welded up hole because the weld will be harder than the surrounding metal.
The rod brackets are welded almost the entire bracket circumference as it sets in the rear end housing. 2 degrees is not that much but need to do it right. You guys have given me a ton of great ideas and are much appreciated. This is my first hot rod build and has been quite the learning experience. Your knowledge and experience are so valuable for guys like myself. Thank you.
A word of caution! You need to check pinion angle at your final ride height!! It will flatten out even more as the spring compresses making your problem worse. That said, from the research I did when building mine, that you want the pivot for the radius rods right below the front u-joint like Johnny Gee suggested. If I were you I would shorten the radius rods and move the pivot back and closer to the u-joint. This will solve your problem.
If you pie cut the bones, you can heat and tweak the spring eyes. Serious question,,, how and why are the brackets welded in if you don't have the ride height amd pinion angle set?? You may be better off to cut the brackets loose and start over correctly. Second serious question, the torque tube counteracts the pinions rolling up response to torque. What's your plan to replace that ?
Another thing I noticed, is that copper you have routed for the brake lines? If so, that is not safe! You must use proper brake line material!
CuNi alloy brake line is about the best material for the application that a guy can get. Not pure copper line though, that's for sure. Hopefully OP replies.
SASROD seems to have the best answer. But here's a question: why the open drive in the first place? Torquetube would have seemed the easiest way to put it together.
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