Really Short Driveshaft?

[boodlefoof]

Hey guys,

Just wondering what people's thoughts are on minimum driveshaft length for a non-IRS rear.

I'm working on my Datsun project (92'' wheelbase) and I'm trying to manage weight distribution. Therefore I've moved the firewall back about 10'' with the intent of moving the engine back. I'm still debating transmission choices, but with a T-56 and the engine set back as far as the firewall it looks as though my driveshaft length will be roughly 25-30''.

Now, had I gone with an IRS I wouldn't be worried. However, I built a Satchell link rear suspension. Now, half-shafts seem to do OK at pretty short lengths... what about a driveshaft?

On my computer model, I can keep the shaft's u-joint angles down to about 5* maximum through my range of motion (max of about 3.5'' bump and 3'' rebound).

Any thoughts?

[boodlefoof]

Anybody? Beuller? Beuller? :D

[69TAPoser]

My Shelby Cobra replica had a 9" drive shaft going into a non-IRS 8.8" Ford rearend. Most cobra replicas are this way due to the tranny sitting so far back. 302 producing 350hp, T5 tranny, and 8.8 rear with 3.55 rear gears. No issues at all.




Phil

[boodlefoof]

Wow Phil! And I thought a 25'' driveshaft would be short! 9'' is short!

[GUS68]

Little jeep wranglers have pretty short shafts and being a 4X4 have, what I thought, some pretty severe angles.