70 Big Block driveshaft
Thread Starter
Limping across the line
Joined: Oct 2002
Posts: 5,299
Likes: 109
From: Peoria Az
70 Big Block driveshaft
Asking a question since I dont see anything listed about it in the NCRS judging guide.
On a 70 BB 4spd car. What is the diameter of the main driveshaft? And should it have U bolts or Caps on the u-joints.
I know the half shafts should have caps but nothing is specifically noted for the driveshaft.
Reason I ask is that my 71 BB 4spd shaft is larger in diam than a 70 BB 4spd cars shaft that I have in the shop rt now.
Also my 71 's shaft has caps at the trans yoke(uncertain about rear ujoint) While the 70 car has U bolts at both ends.
I can see where the 70's shaft has rubbed something in the tunnel so I'm pretty sure you cant put a larger diameter shaft in there. Does anyone know for sure?
May just have to join NCRS to post these questions over there
On a 70 BB 4spd car. What is the diameter of the main driveshaft? And should it have U bolts or Caps on the u-joints.
I know the half shafts should have caps but nothing is specifically noted for the driveshaft.
Reason I ask is that my 71 BB 4spd shaft is larger in diam than a 70 BB 4spd cars shaft that I have in the shop rt now.
Also my 71 's shaft has caps at the trans yoke(uncertain about rear ujoint) While the 70 car has U bolts at both ends.
I can see where the 70's shaft has rubbed something in the tunnel so I'm pretty sure you cant put a larger diameter shaft in there. Does anyone know for sure?
May just have to join NCRS to post these questions over there
Safety Car
Joined: Dec 1999
Posts: 3,605
Likes: 839
From: PA
1968-1970 four speed Corvettes had a driveshaft smaller in diameter than 1971-1972 manual transmission cars... Different universal joints too.
Going from memory, the earlier driveshaft is 2" OD and the later one 2 1/4" OD, but I'd have to measure to be certain.
Automatic transmission driveshafts differed as well (certainly in length), but again, I'd have to check my notes for the details.
If you need specifics, let me know and I'll see what I can dig up.
Regards,
Stan Falenski
Going from memory, the earlier driveshaft is 2" OD and the later one 2 1/4" OD, but I'd have to measure to be certain.
Automatic transmission driveshafts differed as well (certainly in length), but again, I'd have to check my notes for the details.
If you need specifics, let me know and I'll see what I can dig up.
Regards,
Stan Falenski
