Steel vs Aluminum driveshaft

[Ed Carpenter]

Originally Posted by FED 387

maybe no performance advantage but ya are taking WEIGHT outa the car--Comp 387

My car is 65lbs heavy for H. Maybe more if I get some HP off. LOL

[Jim Caughlin]

In case anyone is wondering about weights, my 3" steel driveshaft weighs 13#, the duplicate 3" alum with the same size yoke and ujoints weighs 10#. I didn't do back to back runs so don't have any data on performance differences.

Jim Caughlin
SS 6019

[FED 387]

OK guys not sure what if any performance advantage if there is one but the BIG 3 have been installing aluminum driveshafts in rear wheel drive vehicles from Camaros to Lincolns to full size pick ups/vans etc for about 20 years---there must be a reason they are doing it--anybody wanna guess why a multi billion dollar company would do it?? It aint the color of silver vs. black or rust so why do ya think they are doing it????? comp 387

[Chad Rhodes]

Originally Posted by FED 387

OK guys not sure what if any performance advantage if there is one but the BIG 3 have been installing aluminum driveshafts in rear wheel drive vehicles from Camaros to Lincolns to full size pick ups/vans etc for about 20 years---there must be a reason they are doing it--anybody wanna guess why a multi billion dollar company would do it?? It aint the color of silver vs. black or rust so why do ya think they are doing it????? comp 387

harmonic vibration

[Tom keedle]

Originally Posted by Chad Rhodes

harmonic vibration

yep, that's what they tell me,too.mostly OD trans' have that problem for some reason.

[Jeff Lee]

I had a buddy with a Cummings diesel Ram truck that had a serious vibration problem. Many trips to the dealer and it was a serious problem when towing his race car. The factory finally put a carbon fiber drive shaft in it and curred the problem. I'm sure there is a TSM on it and it can be applied to any mopar car in Stock.

[John Brown]

The real reason that you would what to use a lighter driveshaft is the critical speed for the length of the shaft. Mild steel is good to a certain length where critical speed makes it impractical or dangerous to use in a racing application. Some racers complain about unbalanced slicks when it really is a driveshaft that has exceeded critical speed and has started to whip and bend while going down the track.

My son (a driveshaft engineer for one of the big three) has always told me that you need the lightest, shortest (hard to do), largest diameter driveshaft made from the stiffest material when building a shaft for racing. When you do all these things you raise the critical speed which will add to reliability and increase performance (if you were exceeding critical speed in the first place).

Stockers that have aluminum shafts already can be improved with larger diameter MMC material which again raises critical speed. Stockers with steel shafts can use larger diameter alloy shaft material.

Super Stockers should always adhere to what was stated in paragraph two.

Note: If you want a larger tube make sure that it fits in the tunnel and driveshaft loops before having it made.

If you want more information go here http://www.markwilliams.com/driveshafttech.aspx .

I am by no means an expert on the subject but I can sure talk to one any time when there is a question.

[Tom keedle]

Originally Posted by Jeff Lee

I had a buddy with a Cummings diesel Ram truck that had a serious vibration problem. Many trips to the dealer and it was a serious problem when towing his race car. The factory finally put a carbon fiber drive shaft in it and curred the problem. I'm sure there is a TSM on it and it can be applied to any mopar car in Stock.

i wonder if amc can be included in that