I am building a 1949 Hudson Super, I have swapped the 6cyl and three speed for a Cadillac 500ci and TH400.... I need a 58" one-piece driveshaft. The trans tailshaft is 2 degrees down, pinion is 2 degrees down, when I try to hold a PVC pipe from trans tailshaft to rear pinion, it seems to be 5 degrees down. Engine is 1-2 degrees down. Is this within parameters of a good driveshaft setup or should i get wedges to rotate the rear up and if so, what size wedge to produce what angle at pinion? Thanks Yes i have searched but as yet not got a definitive answer on maximum liveable driveshaft angle. An 8" step in the rear of the model A frame transverse spring . Tail shaft 2 degrees up pinion 2.2 down , driveshaft down from rear to front 9.3 degrees . tailshaft is 10 1/2' from ground ,pinion is 15" from ground. Drive shaft is 27 3/4" long centre to centre. U joint. U joints do appear to bind.
Go to this site (Inland Empire) and give it a read. Tailshaft and pinion both down 2 degrees each will not work. https://www.iedls.com/Power_Train
Is it the original 49 Hudson rear end? They had trouble surviving when the twin carb 308 came along, Hudson went to the Spicer 44 rear in 1953. I just wonder if you might want to change the rear end, in which case you'll probably have to weld on new perches, and you can get them the correct angle. But anyways, you'd want about 3 or 4 degrees of shim to fix the situation you have now. You can buy them at places like Summit, they're called "pinion angle shims". Figure out how wide the springs are, first.
The rear I am taking the angle off of is the stock Hudson rear but I am not intending to use. I am replacing it with Chevy S10 rear. As it looks now, the S10 rear is very close to the same spring pad dimensions, maybe minimal trimming. Should I cut off the mounts and weld them back on at the angle I need them or is it safe to just add the wedges? Thanks Sent from my iPad using The H.A.M.B. mobile app
Not that I would do it but u-joint can work thru 22 degrees. Open a YouTube of an IMCA modified rear end movement. Moog also sells wedges for front straight angle use. 2, 3, 4 degrees. I would keep it within a few degrees. Many car have used offset engines and also to deal with that along with up and down.
are the S10 spring perches the correct width? I'd think they'd be too wide...and I'd probably cut the perches off the original rear, to use on the new rear. And I'd get it all mocked up in the car, and be happy with the driveline angles, before tacking them in place, then remove the rear to weld them. But sometimes I go to a little bit of extra effort to get things right.
If it's that close, then you could probably get away with shims. I like to have the pinion pointing down 1 degree relative, to the engine/trans centerline. So if the trans is down 2 degrees from horizontal, the pinion would be up one degree from horizontal. Make sense? This way, when there is load on the rear springs and they wind up a little bit, the result is that it's parallel. They seem to make less noise this way. How is the overall width, where the wheels bolt on? Close to original? Those cars are really tight under the rear wheel area.
Still watch the hole shots with a S10 rear end. Go with shims as suggested. If you have a TH400 yoke you can mock everything up, but you already have a length and the s10 rear is a known entity. Is that a series 1310 yoke? I had my shaft for my Ford built with a 1310 yoke, I would have slept better with a 1330 piece. The posi I got has a 1310 yoke.
So if I get the pinion up 1 degree, will the fact that the driveshaft is pointing down 5 degrees be ok? Thanks for all your responses BTW... since the pinion is at -2° will I have to get a 3° wedge?
The angle of the driveshaft itself doesn't really matter (it cancels out at both ends). The angle of the engine/transmission center line, to the pinion centerline, is what matters.
Unless I’m missing something, I believe driveshaft angle is important, because it plays into overall u-joint angle at each end. For example, look at the difference in figures 6 and 7 of the the Inland Empire link posted earlier. Here is another link I find useful, but beware it lists all angles as positive https://spicerparts.com/calculators/driveline-operating-angle-calculator There was a thread about this not too long ago that got everyone all frothed up. Not looking for that here, just making sure I’ve got it right and the OP will too.
That's what I was thinking...one driveshaft guy told me to not go higher than 6° He said it was more important to not have more than 1° difference between the trans yoke and pinion. Sorry, I've built a lot of cars but never had one where the driveshaft was at an angle....my anal self wants to do everything correct....old habits die hard! Thank you
Since it sounds like your car is already apart take the time to get your angles correct now so you're not asking about a driveline vibration or u joint wear later. This is one of those things where you do it once and you'll never have to touch it again. In addition to the Inland Empire link I posted there are many good threads on the hamb dealing with this topic if you take a few minutes to search.
Thanks Gasser 57, I've read the IEDLS site front to back...good info. For anyone who might be in the same quandary, I'll share what they and a few other driveshaft sites told me.... My difference between the yoke angle (-2°) and pinion angle (-2°) can be adjusted to parallel angles by adding (4°) shims to the rear axle spring pads, thus solving that u-joint problem. I was told by doing that, the 5° angle of the driveshaft is not a problem and progress can go on. Thanks for the help.
In a "W" configuration you can have two "down" angles. In a vehicle with a very low mounted engine/transmission this is sometimes necessary.
I hear you but what I’m trying to say is that by adding 4° shim to the spring pads I will get 2° up at the pinion. I’ve been told this will work. Thanks
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