I pulled the driveshaft off the '46 banjo that is going in my A sedan and it got me to thinking. Since the rear of the driveshaft is a splined sleeve coupling. How much angle at the motor end is too much? Obviously pinion angle is not an issue when setting up this combo but it is the first time using a banjo rear and I am curious. Also, can you get one out of phase or since you are only dealing with a U joint on one end it that a mute point?
They have no needles, they will function at tighter angles but probably wear faster and aren't as cheap to replace as late model stuff. There is nothing to get out of sync with I know of. Are you considering changing the angle due to lowering the car and therefore the motor? If so, the diff oil go's into the tube and a barrier has to be constructed to keep the mess in the back.
Actually where the car sits right now the driveshaft is about even with the frame rails so I may raise the motor a bit. I like that look, flatheads kind of get lost sometimes when they are set too low between the rails IMHO.
GV, I have no scientific data for you, but I've set a few of these up. I've never had excessive ujoint wear issues and that is with engines set up at many different angles. However, I do know that when the angle is too severe (usually from trying to the the rear end ultra low), there is excessive wear where the torque tube bell mates to the tranny. I've seen that on 3 cars. Not real sure why.
My understanding is there need's to be some offset, at least on conventional 2 joint shafts, there is a harmonic, vibrational thing that occurs if perfect alignment is achieved. That is the reason for the 2 or 3 degrees up or down driveshaft and level engine. I know that tractor PTO equipment could get some nasty whip going on at times, and seem's like going straight through a dip, no load situation when there is a fairly straight alignment. Seem's like there is a street rodder (or some mag) article on the subject around here somewhere...
rodrelic, Yes, but isn't that because there is a u-joint at both ends? On an enclosed old Ford the back end of the shaft splines directly to the pinion. I am not sure, that's why I asked.
Funny, as I was pulling the driveshaft/tube a couple days ago I was having the same train of thought. I never messed with one before either.
Yeah, that is what I am using and the reason I shimmed the trans mount to get some offset. But after further scrutiny as long as there is a good bearing behind the joint, maybe a straight line will work OK. The center bearing is also something to consider. I did not put the center bearing in since the shaft/tube assembly is shortened a bunch. The machineist felt it would work without and it also cost's 300 bucks. If it develops whip then I will have to fit one of them. Should be a side view, but the magnetic angle dangle gauge on the tube show's 2.5 degrees and the level on the intake surface show's level. That is done of course with the correct tire height, in this case 5.25-18" softened up to equal the height of 600-16 fronts now used.
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