Any1 knows anything about driveshafts?

[SFRT - Frenchy]

Building this M37 I don't have much room between the trans and the TC. What would u recommend to connect the two. Would the angle between the trans and TC be stressing the output shaft or TC input yoke too much?

https://www.youtube.com/watch?v=qGnEBw8TL3E

[Skuzzy]

You want some angle in the driveshaft.  It should not be inline with the transmission output shaft and the pinion yoke. 

BUT, and this is a big one.  The output shaft and the pinion yoke MUST be parallel to each other.  You will end up tearing up a transimission and/or rear end if those two are not in parallel to each other.

You want a little angle in the driveshaft so the u-joints actually work.  If there is no angle, the u-joints will seize after running for a bit.  Not a good thing.

My Cobra driveshaft is 11" long.  The shaft itself.  I am going with an aluminum shaft.

[DaveBB]

Why aluminum Skuzzy?  It is a far weaker metal and far more prone to cracking than steel.

[SFRT - Frenchy]

Not if it's designed properly. They even have carbon fiber DS on race cars. It's like a light wheel, light flywheel ... less rotating mass the quicker stuffs spools up 

[SFRT - Frenchy]

Skuzz, what do u mean by parallel. What would u fix?

[Hajo]

Nice job Frenchy!  Looking at the alignment it would put me in a quandary also.  I'd have lots of questions also.  I'd need some professional advice also.  Good luck!  It's a great looking project!

[SIK1]

There is a pretty good article here: http://www.4crawler.com/4x4/CheapTricks/Driveline-101.shtml

It's hard to see in the pictures without an angle finder, but the angles look to exceed the two, or three degrees difference from parallel. (Your output shaft points at the ground while your T-case input looks to be parallel to the ground.) You'll notice in the article I linked that operating angle and shaft RPM have a direct correlation The side to side offset would also be a concern for me because of how short the shaft is, and the resulting severe angle placed on the u-joint. Another thing it looks like you have a fixed output yoke, so what kind of slip setup were you going to use?

If you don't get it right a poorly setup drive shaft will be nothing but a headache, They eat u-joints, destroy bearings, seals and can even ruin the transmission, or t-case/differential. Do it right and it will give you years of trouble free service.


 
Sik

[JOACH1M]

https://youtu.be/gmV4qwLfOMY

Good 2 minute video about drivelines

[SFRT - Frenchy]

It is a great article Sik1. Thank you.

The angle Vs RPM is interesting. The engine will see 3000 max as it's an International. At highway speed with the overdrive of .75 I should be 3750 DS RPM. What trips me is the factory TS to front differential angle is pretty extreme.

[SFRT - Frenchy]

https://youtu.be/gmV4qwLfOMY

Good 2 minute video about drivelines

DS for dummies. Awesome 

[ROC]

DS for dummies. Awesome

Ya,but if you look at the right sidebar, great film on doing the splits! 

[GScholz]

Why not use constant-velocity joints and save yourself the hassle?

[MiloMorai]

Make new motor mounts so the alignment is better.

[Skuzzy]

Why aluminum Skuzzy?  It is a far weaker metal and far more prone to cracking than steel.

My car weighs about 2250 pounds, wet.  The driveshaft is not going to be stressed as much as a car weighing in at 4,000 pounds.  The shaft, itself, is only 11" long.  The shorter shaft is less likely to twist/flex as much as a longer shaft.

You also get less snap with an aluminum shaft.  Steel does flex more and that flex can cause stability issues when you are on and off the gas a lot.  It acts like a spring winding and unwinding all the time.  You are right.  Aluminum will crack when steel will flex, but it is a low risk in such a light car.


Frenchy, I assume you got the answers you needed from the various links.  That pinion yoke angle seems really extreme.

[Shuffler]

3000 series aluminum  is very flexible. 6ooo series has minimal flesh but is more brittle.

For aluminum boxes we use 5052, bends well and is strong. For sub panels we use 6062 as it is stout for mounting things. 3000 series is seen on grass farms and such on the big wheel sprayers. The pipe flexes all over and does not break.