Aluminum Driveshaft, worth it?

[stonegod85]

so what about AODE's....can we have aluminum driveshafts or what? i was told that the automatics have a shorter shaft than the manuals and that you have to buy some kind of spacer for it to work properly.

 

[lgndracer]

the aluminum only weighs 3 #s more...I mean what a 1/2 HP difference? LOL. Ill just get aluminum when the time cames...im sure ill get a good 4hp then.

You have to look at exactly what you are trying to do. There are two basic ways to make your car "faster". More power, or increasing your power to weight ratio. The lightening of items increases your power to weight ratio. This is why a lighter less powerful car (SRT4 for example) can hang with a much more powerful V8, yet heavier (Mustang GT) car.

I raced late model stock cars for about 12 years. Our philosophy always was "ounces add up to pounds", meaning anywhere you could lighten anything would add up to reducing the overall weight of the car. We would always try to be "underweight" for our rules, so we could go back and add weight where we could get the most transfer or traction. This applies to all forms of performance, whether you are circle track racing, road racing, or drag racing. Why do guys take out their spare when they run the 1/4? Same idea.

Also, the drive shaft is "rotating weight", so it being 3 lbs lighter is a lot, as it takes less to get it moving. If you are going to try and reduce weight the two places that will make the most difference are "rotating weight" (wheels, brake rotors, flywheel, driveshaft, axels, engine internals) and "unsprung weight" (suspention components, brake calipers).

Just my .02

 

[JohnyD05]

Exactly. Aluminum is just automatically more predisposed to breakage under torque than steel, that's all.

I don't agree, Pound for pound I believe Aluminium has a higher torsional strength then steel.

So I sort of take that back,
While pound for pound this is true, i believe something the same dimensions, steel has the advantage, check this article out.
http://ussautomotive.com/auto/steelvsal/basicfacts.htm

Also They point out steel handles Fatigue much better than aluminium. This could support your theory that aluminium drive shafts are more likely to break. Either way a driveshaft safety loop is cheap, and if your down there, theres no reason not to have one. Unless you really like to do the pole vault in a car.

 

[JohnyD05]

I've dyno'ed my car to see how much gain for an aluminum drive shaft. The results were 0rwhp gain and a gain of 7rwtq.

I don't see how this is possible...

Hp takes into account how fast you can essentially spin the dynomometer drum. So you should be able to spin it faster with a lighter driveshaft.... therefore more HP

As far as torque the ultimate torque your engine should produce should be the same, it might just take longer to get the right RPM to produce that torque.
Is there any way that you had other mods done more than just a driveshaft?

does anyone else follow my logic, or am I crazy?

So i am bored at work...

And after thinking about it, the Torque should also change, but it should not depend on the RPm. You should have the same TQ gain throughout the RPM.

 

[JohnyD05]

so what about AODE's....can we have aluminum driveshafts or what? i was told that the automatics have a shorter shaft than the manuals and that you have to buy some kind of spacer for it to work properly.

I am not positive, but i think you have to specify wether you have a Auto or Manual because of the driveshaft length... I could be wrong though. My shaft is stock.

 

[stonegod85]

well i haven't been able to find aluminum driveshafts that are FOR auto's....only listed ones are for the manuals. this is why i kinda think there may be some sort of "adapter peice" for the shaft to work on an auto. i've tried to search on this several times and i can never get an answer...just thought i'd throw my thought out there.

 

[hognutz]

I would do subframes and lower control arms first. that is me though.

that I might think about it.

 

[hotmustang331]

You have to look at exactly what you are trying to do. There are two basic ways to make your car "faster". More power, or increasing your power to weight ratio. The lightening of items increases your power to weight ratio. This is why a lighter less powerful car (SRT4 for example) can hang with a much more powerful V8, yet heavier (Mustang GT) car.

I raced late model stock cars for about 12 years. Our philosophy always was "ounces add up to pounds", meaning anywhere you could lighten anything would add up to reducing the overall weight of the car. We would always try to be "underweight" for our rules, so we could go back and add weight where we could get the most transfer or traction. This applies to all forms of performance, whether you are circle track racing, road racing, or drag racing. Why do guys take out their spare when they run the 1/4? Same idea.

Also, the drive shaft is "rotating weight", so it being 3 lbs lighter is a lot, as it takes less to get it moving. If you are going to try and reduce weight the two places that will make the most difference are "rotating weight" (wheels, brake rotors, flywheel, driveshaft, axels, engine internals) and "unsprung weight" (suspention components, brake calipers).

Just my .02

I agree completely. My WHOLE problem is, "hmm do I want to spend $800 more just to maybe gain 2HP?" . I realize that every little bit helps, but gosh dang im not made out of money . I can put that 800 towards something that would help more than .02 in the 1/4. I would say that the CF drive shaft is for A. someone who is not conserned with cost and wants EVERY last HP. B. someone who has done EVERYTHING and has nothing left to do. C. someone who just wants to include his drive shaft in his long list of carbon fiber parts.(ricer)

 

[BMan5150]

I got an aluminum ds simply because I got it for $149 (think they are more like $199 now or higher). I got it primarily because I never wanted any vibration problems. I do think the alum ds increases the amount of gear clash/noise into the car than the steel ds did. I wouldn't be able to tell you if I felt the effect of the alum ds because I did 4.10s at the same time. My bet is that it does next to nothing for the average joe occasional drag racer like me and most of the other people on this ubb. Get it if you want to get rid of the ds vibration (or try rotating your ds to get rid of the vibration first). I probably would have been better off spending that $149 on beer, but then again I have no driveline vibration!

 

[xseler8]

I would do subframes and lower control arms first.


These are essential. Good mods.Money well spent.
Also..back to the drive shaft loop. Anyone that races..get one. And get the type that will accept the aluminum DS when it is upgrade time.

 

[MYSLO4-6]

well i haven't been able to find aluminum driveshafts that are FOR auto's....only listed ones are for the manuals. this is why i kinda think there may be some sort of "adapter peice" for the shaft to work on an auto. i've tried to search on this several times and i can never get an answer...just thought i'd throw my thought out there.

The shop where I get all my work done at and the local FRPP Dealer said the the aluminum ds will work with a auto, but you must change the yoke at the end of the ds because it is a different spline count than a manual. I know this because I'm getting one for my auto. Just call your local FRPP dealer and ask.

 

[Chris00GT]

I don't see how this is possible...

Hp takes into account how fast you can essentially spin the dynomometer drum. So you should be able to spin it faster with a lighter driveshaft.... therefore more HP

As far as torque the ultimate torque your engine should produce should be the same, it might just take longer to get the right RPM to produce that torque.
Is there any way that you had other mods done more than just a driveshaft?

does anyone else follow my logic, or am I crazy?

So i am bored at work...

And after thinking about it, the Torque should also change, but it should not depend on the RPm. You should have the same TQ gain throughout the RPM.

I'm just reporting what it gained. This was about 5 years ago so I don't have the graph, but I dyno'ed the car in the morning and then installed the drive shaft and re-dyno'ed it..gained 0hp and 7lbs of torque. The only reason I remember this is the was the only time I gained 0hp from a mod. This is back in the day when I played with all kinds of N/A combo shooting for more power. It was nice to have a dynojet at work to play with

 

[white-04]

I've read in prior posts regarding AL driveshafts that the increased diameter of the AL driveshaft affects its effectiveness. Someone with a better grasp of Physics can explain it better than me....or try to find it in search....

 

[menasci]

Ford Racing aluminum driveshafts will reduce the rotating mass of your car and allow you to put more horsepower to the ground.
Aluminum Driveshafts increase the critical shaft speed, (the RPM at which the shaft will go into harmonic vibration and risks self destruction).
There is also a reduction of amount of torsional wind-up, that can have a profound improvement on reaction times.
The aluminum shaft has many advantages over the steel shafts.
The most obvious, is the fact that it is 1/3 less in weight.
Another advantage is that its resonant frequency properties are much higher, which means a steel shaft may amplify a vibration, where as an aluminum shaft will dampen a vibration.
Another thing, is that an aluminum shaft will torsionally twist 19 degrees and a steel shaft will only twist 5 degrees.
This means an aluminum shaft will have a more dampened affect, taking the shaft load out of the drivetrain, making it more fluid feeling.
Yes, this was copied and pasted from several websites

 

[hotmustang331]

Dang, you guys are going to make me spend more $$$ . SOOOO wheres the cheapest place to buy one? And that 19*s means its going to bounce back, so on initial launch it will save the axles, but then bounce back and propell you forward. NICE!