I got the 'Strange U1699 driveshaft 3"x.083" DOM chrome moly driveshaft with H.D. U-joints' From Strange to go with my Dana 60. The thing feels like it weighs a ton, I did not have a scale..but felt at least twice as heavy as my stock aluminum one.

Does anyone know anything about this driveshaft, and how many horses it's going to cost me?

 

I'm also wondering this. Would it be cheaper or even practical to have the stocker shortened?

 

this site compares stock steel to aluminum 1le shaft...

and they saw 1hp and 5#s of torque

i would think it would be similar, but in reverse for your application.

 

Yes, I have read that before. So, you think I lost about 2hp and about 10 torque?

 

If you have enough HP/torque to require the S60, you definitely need something a bit beefier than the stocker. Do NOT try to save weight/HP with a flimsy driveshaft.

I bought the ultimate in HP savers with an ACPT HD carbon fiber DS, top of the line, expensive as hell, and it failed when the car was being driven with a "just enough to keep it running from the engine shop to the body shop" tune. I can't imagine the destruction if that thing had let go under a launch or dyno pull with a 300-shot of nitrous. I immediately bought a Mark Williams 3" chrome moly DS. Chrome moly weighs about 30% less than the same strength DS made out of mild steel.

How much does the Strange DS weigh? I suspect its about 19#.

 

I'm not sure how much it weighs, I can't find any information on it.

I was thinking about staying with a aluminum weak driveshaft and setup two good DSLs, and use the DSs as 'fuses' to protect the unbuilt tranny.

Don't you think it's possible your CF DS broke from a defect? I just don't see how a proper working DS rated for 600+ hp would snap from casual driving, but carbon fiber is such a directionally strong material I can see how any flex at all, or a misalignment would of done it. If you did snap it at the track I would think the damage would be pretty low...doesn't carbon fiber pretty much just disintegrate when it comes a part?

 

If you can use an aluminum DS, you just wasted a lot of money on a Dana 60.

Rich

 

10 bolt can't hold stock power, how did I waste any money?

 

There shouldn't be any need to worry about the tranny with your setup.

 

Did you break a stock rear with a stock motor? Yeah, I know that can happen but I can't see deliberately makes the DS the "fuse". You need a DS that is as strong as the rest of the parts, or you will then be breaking DS's instead of rear ends. They are cheaper though.

A DS, even if it's heavy, has the mass close to the the CL and isn't turning that fast. So it doesn't rob as much power as you might think.

If you really want an Al DS, get this one: http://www.dennysdriveshaft.com/html/hd_aluminum.html

Rich

 

My rear never actually broke, but the axle bearings were shot and had a lot of miles on it. I had never put slicks or gear sin the car because I didn't want to break it...so I got a cost effective upgrade that should be able to handle anything I ever do to the car. Right now I will be launching on slicks with 500rwtq. I know an aluminum DS won't take that, but I thought a stock steel one might.

My theory behind his DS fuse thing is if something is going to give, I would rather it be the DS than the tranny...until I get it rebuilt that is.

 

I generally weigh parts on my bathroom scale before I install them. My Strange 12-bolt weighed 165# wet, only a few # more than the stocker. My 3" chrome moly DS weighed 19#, compared to 15# for the stocker, and 9# for the CF.
I'm sure it broke from a defect.... the front yoke started to spin in the CF tube. My theory is the glued joint between the yoke assembly and the tube was not cleaned properly.

The point I was trying to make is that a DS is not a place to try and save weight to save HP. Going to aluminum saves weight, and gives you a weaker DS. Going with CF saves you a lot of weight, but leaves you open to problems with something that is related to aerospace technolgy, particularly the bond between the yoke and the tube, and the extreme levels of cleanliness required. Don't gamble on the DS.

As far a damage, you're right..... if you only look at the DS. The way mine failed, it did no damage to anything (except my wallet, and the 4 months it took me to grind the ACPT engineer into the ground to the point of admitting it was defective). But think beyond the box.... or in this case beyond the DS. Consider an engine capable of producing 800 lb-ft at the flash stall of the converter, and being multiplied by the torque stall ratio of that converter. Think about an engine that is ingesting a 300HP shot of nitrous and fuel through 78#/HR injectors. Think what happens to that engine the instant the load is removed, by DS failure. I doubt the best rev limiter in the world will respond in time to save it.

 

That's a very good point, I didn't think past the obvious damage the DS would inflict to the bottom of the car.

 

It may also lunch the motor or cause an accident.

Rich

 

Broken driveshafts also break transmission cases and tailshafts, been there, done that.

Out of curiousity, if you're worried about losing HP for the steel shaft, why did you choose a dana 60? Both a 9" and a 12 bolt are lighter, more efficient, and have less HP loss than the dana.

IMO, just run the steel shaft, and abuse the car as hard as you want without worry. That's the whole point of a driveline upgrade, right? I have a moser 9 and similar steel driveshaft in my elcamino, and don't think twice about popping the clutch at any RPM. Really allows a person to enjoy the 3rd pedal.