razorback

ok i have a question and its pretty much what are driveshafts usually made of? the type of metal and such.

jimlab

Steel, aluminum, and carbon fiber. Take your pick.

razorback

thanks.

razorback

where can you get the parts for a custom driveshaft? will normal round steel work?

jimlab

You have one built for you. A driveshaft is not something you want to try to piece together for yourself.

Start here... www.dennysdriveshaft.com

razorback

where did you get your driveshaft from?

jimlab

I will be getting mine from Denny's, which is where I got my billet transmission yoke. All I need is the overall length, and I won't know that until the engine and transmission are in the car.

razorback

how much longer until completion?

which "model" are you going for of driveshafts that they offer?

jimlab

Unknown. I don't really care much about getting it done, and I'm far too busy to do much work on it these days.

The heavy duty (HD) aluminum. Denny's said that the "nitrous ready" driveshaft was overkill for my application and was intended for 1,000+ horsepower in a 3,500+ lb. car.

razorback

im asking because i have a mopar 383 and a 727 transmission that i may put in my fc. im sure it will fit but i just have to see tomorrow if the motor is froze up. if it isnt then i will pull it and use it for either in my car or something else down the road. if it is froze up then i may have it bored to the max and get oversized pistons. either way i know im going to have to get a beefy rear end (plan on doing other stuff to it later down the road i just want my damn car running again) i still like rotaries but i cant find a decent motor around here for a rebuild. and i really dont want to go the jspec route and wait 3 months for a motor. thats why ive been asking.

you and your wife had/have a kid on the way correct?

jimlab

8 months old yesterday. They take up a lot of your spare time, not that I have much anyway.

razorback

wow congrats.

Cory Simpson

You don't have to order your driveshaft off of the net.


I had a custom one made for $150 at a local driveshaft specialty shop, called "master fabricators" They used the front yold of one driveshaft, and the rear of the RX-7's driveshaft, and found the rear half of another yolk that would work (because RX-7 U-joint's are non-replable.)


Just call around in your local area, call custom car shops, and ask them if they know of anyone that does that. They usually will.


Also when ever you make a driveshaft, always leave about 1-1.5" of play. (Just a little tip.)

jimlab

That depends on whether you're just having one built for a car that may only see 100+ mph occasionally or if you need one perfectly balanced for sustained higher speeds.

I'm sure your local shop is just fine if all you want is a tube to connect the transmission to the differential, but I'd rather go to someone with the equipment and experience to build a driveshaft that isn't going to come apart at 150+ mph.

razorback

motor not froze up..one step closer

Cory Simpson

Do you know anything about the shop I had my driveshaft made at? NO!

They don't just cut/weld it together. They rebalanced my driveshaft after they made it to what I needed.

They specialize in making/repairing driveshafts, it not just a little po-dunk welding shop.

jimlab

Do I care? No.

Good for you. What rpm did they certify it for?

travisorus rex

I know that carbon fiber driveshafts are available. My question is, do they have the same effect as a lightweight flywheel?

I have a friend that makes carbon tubing for a living (cool military stuff) and he seams to believe that it would be strong enough but I am still skeptical.

jimlab

To a lesser extent. The weight savings isn't as significant.

They can be, but the fringe benefit of a carbon fiber driveshaft is that if it breaks, it tends to fray (often referred to as "broomsticking") and do very little damage to the car, whereas a metal driveshaft can cause serious damage. Without a driveshaft loop, a break towards the front of the driveshaft could literally pole vault the car into the air.

ACPT is one of the larger manufacturers of carbon driveshafts. Here's a link to their site where you can find more information...
http://www.acpt.com/driveshaft/driveshafts.html