Good recommendation on a driveshaft...?

Guys,

Who would you recommend for a driveshaft? Should have around 750HP and turn around 7500 max...

I had one made at a local truck shop, it was 200 bucks w the 1350 joints, I supplied the trans yoke. Its a 3.5" ms deal.

I can go that route too. Any certain wall thickness I need to ask for? Or just tell them I need a 3.5" shaft?

I use Midwest driveshaft. 1350 joints, strange yoke.

dfree383 wrote:I like strange

We knew this already...

We prefer 3.5" Strange seamless CM with billet ends. I don't like to have to worry about a driveshaft stabbing me. It is also shielded like a promod.

I have the enclosure to put it in. Just need to decide on a shaft so I can get the enclosure installed, finish the tinwork, etc...

richter69 wrote:I had one made at a local truck shop, it was 200 bucks w the 1350 joints, I supplied the trans yoke. Its a 3.5" ms deal.

x2

Same as Jon and Blake here. 3.5" O.D. and .083 wall...

I have a 3.5 out of a Mark 5 Linc

what is your peak drive line rpm and what is the center to center length? how much torque do you make and what is your low gear ratio.

i build drive lines every day. i can help you figure out just what is required to make it work.

Center to center length is about 52". Not sur eon the torque. The closest dyno is about 3 or so hours away... It's a 514 w/P-51 heads. Should be around 750ish on the HP.

1.80 1st gear and no more than 7500 on engine RPM.

for your 52" length the critical speed is 7400 rpm for a 3.5" .083 wall tube. for a 4" .083 tube critical speed is 8800 rpm.


Critical Speed is the RPM at which the driveshaft reaches its natural resonant frequency.


from wikipedia,
critical speed: "In solid mechanics, in the field of rotordynamics, the critical speed is the theoretical angular velocity that excites the natural frequency of a rotating object, such as a shaft, propeller, leadscrew, or gear. As the speed of rotation approaches the object's natural frequency, the object begins to resonate, which dramatically increases system vibration. The resulting resonance occurs regardless of orientation. When the rotational speed is equal to the numerical value of the natural vibration then that speed is called critical speed."


rules of thumb for rotaing shafts:
bigger diam. = higher rpm, small diam. = lower rpm
short length = higher rpm, long length=lower rpm.
lower weight = higher rpm, higher weight = rpm.


if you plan on running 7500 rpm in high gear, i would suggest a 4" .083 wall tube.


i hope this helps,
barry