steel or aluminum driveshaft?
 

Is there a measureable advantage for aluminum over steel driveshaft? Is one more durable? This is a SS car.

Re: steel or aluminum driveshaft?
 

I ran a back to back test when I swapped over, steel driveshaft weighed 16#, alum was 13#. Zero performance improvement.

Jim Caughlin
SS 6019

Re: steel or aluminum driveshaft?
 

Maybe 1/2 a tenth max in my car , steel is more durable , if something rubs on aluminum it's gonna break.---Trevor

Re: steel or aluminum driveshaft?
 

I've had both Indy car, saw nothing.

Re: steel or aluminum driveshaft?
 

No performance difference between the two seems reasonable considering the rotating radius is very small.

This seems to me a good part to slightly lower cost of a build up without any downside in performance.

Re: steel or aluminum driveshaft?
 

Its a function of rate of acceleration and rpm.


If you spin your stuff to 9-10,000 rpm aluminum or carbon might be for you, but you must have the total package to see any measurable gains, lightweight clutch, flywheel, axles, spool, ect....anything that spins.


If you have a 5 or 6' long shaft, aluminum or carbon might be for you.


BUT.....with that being said, if you have a converter full of fluid that spins (like what's in a mini van) save ur money, as there is too much slippin'/slidin' and torque multiplication and weight going around to make most lightweight driveline components worthless.


I would have Carbon in mine if the rules allowed it:D

Re: steel or aluminum driveshaft?
 

I've had both steel and aluminum in my car also, with no noticeable improvement. An aluminum driveshaft looks cool, but I think it's one of those things that in theory makes a lot of sense, but in practice really doesn't make any difference.

Re: steel or aluminum driveshaft?
 

There have been several heated threads on yellow bullet; if there is any consensus, it is that the e.t. improvement is slight. I think the bigger point is the critical speed of the shaft, which is a function of length, diameter, and material.

Re: steel or aluminum driveshaft?
 

Same issue with lightweight rearend parts, gundrilled axles, alum spool, lightened ring gear, no noticable improvement. On the other hand, lighter weight flywheel and clutch made a huge difference. In my case, this is a 4 cyl motor that crosses the finish line at 9200.

Re: steel or aluminum driveshaft?
 

Some good reading on the subject:

http://www.dragzine.com/tech-stories...for-your-ride/

http://markwilliams.com/driveshafttech.aspx

Re: steel or aluminum driveshaft?
 

Mark...go to the Mark Williams website and look up "critical speed"..... while a performance improvement is nice you need to spec out your driveshaft based on your trap rpm you achieve.....the diameter and material type will be decided once you have your shaft length and trap rpm....


as an example for my stocker build I needed a shaft 54" long and needed to handle at least 7000 rpm and since it had to be steel I required a 3.5" chromoly shaft.....while aluminum can give you a higher critical speed it is less durable.....


D L Rambo.....Stk 1300

Re: steel or aluminum driveshaft?
 

If any gains are to be had you should see it by using all the parts.


You have met the required parameters.... rpm, 4cyl power, ect. all those "should" improve your performance, results speak louder than theory though

Re: steel or aluminum driveshaft?
 

Carbo fiber. Don't know about improvements in performance, but takes the shock out of the driveline, and is way safer. Ran a 6.20 rear gear for over 100 passes at 3040# with a 5 speed.

Re: steel or aluminum driveshaft?
 

I agree that carbon fiber is probably better but not legal in SS.

Re: steel or aluminum driveshaft?
 

I see a few comments about durability concerns with aluminum. Maybe I have been lucky but I have ran a Dynatec aluminum shaft for several season in my car. 3350lbs run 1.11 60' and have not had any issues at all. I do agree that the performance gains were minimal at best compared to a chromemoly shaft.

Re: steel or aluminum driveshaft?
 

Swapped the stock 3" driveshaft in my 3880 lb. Chevelle back in '99 for a 3 1/2" MMC driveshaft from Denny's, worth .04 in the 1/4. Put thousands of passes on that driveshaft without issue or failure and it's still in the car today. Ran a best of 1.28 60 foot with it and well into the 9's.
http://i381.photobucket.com/albums/o...n6-15-08-1.jpg


Further, my 3144 lb. MPR Firebird has a 4" aluminum driveshaft and has been 1,17 60 foot and well into the 8's also without issue or failure.

Re: steel or aluminum driveshaft?
 

I really think it depends on the application. I swapped a steel for an aluminum driveshaft at the track for a back-to-back comparison and gained absolutely nothing. The added bummer was that they were checking driveshafts at that very race. They wound up banning them at the end of that year in Stock Eliminator, unless they were OEM for the particular car.

Re: steel or aluminum driveshaft?
 

plastic

Re: steel or aluminum driveshaft?
 

I changed from a Strange light weight steel spool to aluminum, lightened ring gear, and aluminum driveshaft. My car is evidently dumb, because I saw zero. Well, actually, I lost first round at the last race I ran at Memphis when it cleaned the right side splines out of the spool on the starting line. About got the tree.

Still have the driveshaft. Steel spool stays in it now, and I don't spend money on lightened ring gears.

Re: steel or aluminum driveshaft?
 

I was told a story about Kip Martin (RIP) and his Super Stock Mustang.
Kip ran an Aluminum drive shaft which broke at a race.
I was told he found a steel replacement and his car slowed down a few 10th's and MPH.
As soon as he replaced the steel unit with an Aluminum one, he gained back his ET and MPH.

Also, as I understand, Stephen Johnson replaced his steel unit with Aluminum and also picked up ET and MPH on his Fairline.

Re: steel or aluminum driveshaft?
 

As they say on television, "Your results may vary". All I can say is that a low HP combinations like mine, particularly spinning the driveshaft up to 9200 RPM at the finishline should be the most likely candidate for improvement and I got zip. For what it's worth, this was a back to back test so I'm pretty confident of my results. Funny thing is that if I was going to start over, I would buy the lightweight parts regardless. I know in my mind that it has got to be better even if the performance results don't show. At the very least, the weight reduction results in less unsprung weight and allows more static ballast over the rearend.

Jim Caughlin
SS 6019

Re: steel or aluminum driveshaft?
 

I always A-B-A stuff like the driveshaft at the track, same day. I did not the spool. Spent that money, and the lightened ring gear, figuring it HAD to be worth SOMETHING. But it was less than 5 lbs lighter than the lightened Strange steel spool. Mine only runs 8500 in the lights.
It ran the weather station predictions equally with both spools.

Re: steel or aluminum driveshaft?
 

I've often wondered if the reason that lightened axles,driveshafts,etc. don't show an increase in performance is because of the short distance we run.In other words if you made the same weight saving modifications to a Bonneville salt flats car, it has a longer period of time to effect the car.Of course they don't measure E.T.and I could be wrong also.

Re: steel or aluminum driveshaft?
 

The diameter on the weight difference makes a difference. 5lbs on a spool, or an even smaller diameter driveshaft is all that much change in inertia. Five pounds on a 32" tire, for instance, is a different deal. I have a pair of Goodyear radials, same size as my MTs, but five pounds per tire difference. Hook just as hard. Consistent four hundredths slower than the Mickys. Three of it in 60'. I can't imagine how it could be anything but weight.

I spent money to get six more pounds off a crankshaft during a freshen up also. Saw nothing. A very low hp engine? Maybe.

Re: steel or aluminum driveshaft?
 

can anybody see a reaction time difference with changing to light weight driveline componets ? I would think it would be very small if you could gauge it at all.

Re: steel or aluminum driveshaft?
 

Like it has been shared on this discussion by many, there are lots of variables involved. One of the main gains that many have seen is switching to lighter rear wheels.

Re: steel or aluminum driveshaft?
 

Yeppers, or rear tires.

Re: steel or aluminum driveshaft?
 

What are the wights of the this 3, 9x30 radials?
Hoosier
M/T
GOOD YEAR

Re: steel or aluminum driveshaft?
 

Can't comment on any performance increases, I've always bought the lite stuff. On a new build I'd say pay the extra money and go lite, not sure if I'd purchase "extra" lite components trying to improve performance. In my opinion engine upgrades, convereter, gearing would be a better place to spend that money.

Re: steel or aluminum driveshaft?
 

Glen, I don't use 9" tires. I have no idea.

Re: steel or aluminum driveshaft?
 

MEXJOE---- about 22.7---23 pounds per tire depending on the brand--FED 387

Re: steel or aluminum driveshaft?
 

Use aluminum

Re: steel or aluminum driveshaft?
 

the use of JUST a steel or aluminum driveshaft alone is not going to give you any significant reduction in ET--- however when used in conjunction with many other "performance/lightweight" parts the overall performance of a particular vehicle should improve. It all depends on the parts selected and the individual vehicle-- some will see improvements while others may maintain the status quo or its even possible that your performance "may" not be as good as before---- it also might just contribute to parts longevity.--there is no firm answer to this question--- in some instances steel is the way to go while in other situations an aluminum driveshaft is the answer--you just have to experiment and observe what a " quick" similar classed vehicle is using and how your performance compares to that one--- FED 387

Re: steel or aluminum driveshaft?
 

If nothing else, I think it may soak up some shock to the gears in a Trans brake or stick car.
And a steel spool may be enough more rigid to improve gear set life.

Re: steel or aluminum driveshaft?
 

I've won and lost by .003. If you are in this game to win, you do it all. Everything!

Re: steel or aluminum driveshaft?
 

Here's one answer I got a couple years ago about lightweight parts!


We didn't see anything. I remember Joey Wilkes did everything. Gun drilled MW 40 spline and all. It slowed down...Ask him about it. It was kinda funny at the time, ( Even he was laughing)

__________________
Jeff Niceswanger 3740

Re: steel or aluminum driveshaft?
 

Steel is ugly. Aluminum is pretty.

Re: steel or aluminum driveshaft?
 

Depends on the painter.

Re: steel or aluminum driveshaft?
 

You never know when it might make the cover.