Ford Muscle Cars Tech Forum banner

1 - 11 of 11 Posts

·
Registered
Joined
·
147 Posts
Discussion Starter · #1 ·
I've got a 1973 F-100 longbed with the two piece driveshaft (bearing at the center), 351W (a swap from a 302), C4 (built), and stock 9" rear. I'm doing some engine work that will raise power to nearly 400hp. I'm a bit concerned about the strength of that 2 piece shaft setup (factory stock). Wondering if I can upgrade it somehow. I was told not to go to a single shaft setup because of the wheelbase (133&quot
.

Any ideas?
 

·
Registered
Joined
·
401 Posts
my 1979 F100 long bed with 351M/C6 and a 9" had a "One Piece" drive shaft from the factory. although your C4 may require a longer shaft due to a possible shorter transmission.
 

·
Registered
Joined
·
147 Posts
Discussion Starter · #3 ·
rustedduster, what length was your wheelbase? Also, does your tranny have the slip joint at the end of the tailhousing? My rig has the bolt-on yoke at the end with the slip joint at the free running bearing in the middle of the shaft. That sort of precludes using a single shaft. I was just concerned of my setup can handle...say 400hp?

<font size=-1>[ This Message was edited by: polkat on 11/15/06 9:29am ]</font>
 

·
Registered
Joined
·
401 Posts
not sure on my wheelbase. the truck is a std. cab longbed. i do have the slip yoke at the transmission. im also not too sure how much your shaft will handle. im not very familiar with your type of setup. sorry i couldnt be more help.
 

·
Registered
Joined
·
147 Posts
Discussion Starter · #5 ·
No problem! Mine is a '73 longbed with 133" wheelbase. Others I've seen from the same basic year are also 2 piece with bolt-on yokes. maybe they changed a few years later. The shaft is plenty strong. My concern was with the free running bearing in the middle. Doesn't seem like the strongest idea, but then again, with a full load (1000lbs) it holds up pretty well. I won't worry about it. Thanks!
 

·
Registered
Joined
·
3 Posts
some of those trucks from'73 to '79 came factory with a one piece driveshaft. i had one in a '77 F150. it was strong enough to handle anything i threw at it. I prefer one piece to the carrier bearing set up. u-joints, ive busted. but have never broke the shaft itself.
 

·
Registered
Joined
·
147 Posts
Discussion Starter · #8 ·
cruizerdude, that's exactly what I'm concerned about. I haven't broken anything yet, but as the power goes up...who knows. One driveshaft shop I talked to said that since my wheelbase is 133", a single shaft would be too long! I'm not convinced of this, but I'm also not convinced that the two piece setup couldn't be made stronger.
 

·
Registered
Joined
·
4,154 Posts
for what its worth, my dads 88 E350 with who knows how long of a wheel base had a 1 piece shaft behind a 460-C6. Just make sure and recheack your pinion angles if you swap.
 

·
Registered
Joined
·
2,334 Posts
I had a 72 ext cab long box 2 peice drive shaft behing a pretty stout 351 cleavland and never had a problem. Shelled transmissions but never a drive issue just be sure to keep an eye on the carrier bearing and just do general maintenence, after all these shafts are made for towing etc so they take more abuse than a car shaft ever would with the jerking forward and back that a loaded trailer creates
 

·
Registered
Joined
·
214 Posts
MY 71 F100 long bed regular cab came with a 302/3 sp. It had the 2 piece shaft but after swpping in the 351w/aod I went to a 1 piece. I later went to a 460-c6 and had another 1 piece made to fit this set-up. The driveline shop said that my drivesahft was about as long as he would go on one and would'nt promise it would balance right. It did balance good.
clint
 
1 - 11 of 11 Posts
Top