aluminum drive shaft - anyone?

[D K]

Originally Posted by Wyattkb

So no input on whether the one piece drive shafts causes any premature wear on any parts?

might cause premature wear on tires

[stugray]

Originally Posted by Hawk77FT

Look up the Grimmspeed research on lightweight weight pulley!

Look up the research that shows immunization causes autism.

[Dimman]

Originally Posted by stugray

Look up the research that shows immunization causes autism.

Organic food causes autism.



On a serious note, the guy in the anti-rotational mass blog does make a couple of statements that support benefits of reducing rotating mass.

In his summary he states that he would rather spend his money reducing static weight by 60lbs than on the HP absorption of the rotating mass parts. But those also have weight savings that total 47lbs which also contribute to static power to weight.

The other thing, which has been noted above, us that he is focused on drag racing with uninterrupted acceleration pulls in the 11-13 seconds ranges in his examples. Where we are focusing on the go. But he also states:

Now a lighter shaft certainly can help in a very light vehicle. It can also help in a road race car (as will a light crank and flywheel), because road racing requires instantly changing from acceleration to deceleration.

The lighter you get, the more benefit you see. And in anything but steady state acceleration pulls you will also see a benefit. And you STILL get the static weight decrease.

Look pretty beneficial to me...

[stugray]

Originally Posted by Dimman

Organic food causes autism.

Originally Posted by Dimman

On a serious note, the guy in the anti-rotational mass blog does make a couple of statements that support benefits of reducing rotating mass.

In his summary he states that he would rather spend his money reducing static weight by 60lbs than on the HP absorption of the rotating mass parts. But those also have weight savings that total 47lbs which also contribute to static power to weight.

The other thing, which has been noted above, us that he is focused on drag racing with uninterrupted acceleration pulls in the 11-13 seconds ranges in his examples. Where we are focusing on the go. But he also states:



The lighter you get, the more benefit you see. And in anything but steady state acceleration pulls you will also see a benefit. And you STILL get the static weight decrease.

Look pretty beneficial to me...

I have never said there is no benefit.
I just call horseshit when people claim they can tell with their butt dynos a difference when replacing a crank pulley. It is in the noise.
If you can detect the difference between the stock pulley and the LW CP, with your ass, then you sure as HELL should be able to notice the difference between a full gas tank and one that is down by just ONE gallon (hint: you cant).

[D K]

I can tell when my windshield washer fluid is getting low

[zdr93523]

Originally Posted by Poodles

The center joint has nothing to do with this... The driveshaft more likely has a bonded section in one of the shaft pieces. Eliminating that would achieve the same feel.


I'm waiting for someone to make a light weight 2-piece...

"more likely" as in, you don't know.

[Captain Insano]

Originally Posted by D K

I can tell when my windshield washer fluid is getting low

So can I.....



The little warning light comes on.

[Poodles]

Originally Posted by zdr93523

"more likely" as in, you don't know.

Yes, I don't know if it has a bonded section, but I do know the center bearing doesn't "load up" like you say.


From photos (as I haven't crawled under my car to look), it appears the bonded section is in the front part.


Also, steel is used because it's the most durable and won't work harden. Carbon fiber is outside the price point this car was aimed at. Carbon driveshafts are very strong, have a high critical speed, and when they do fail, they just become a broom. Downside to them is that rock chips can easily weaken them.

[Pete156]

Originally Posted by FirestormFRS

Driveshafts are not unsprung weight...Rotating mass.

Negatives more NVH normally. The two piece won't fold up and jam you in the ass in a severe rear end crash.

Actually some of the driveshaft's weight is unsprung, is it not?

[zdr93523]

Originally Posted by Poodles

Yes, I don't know if it has a bonded section, but I do know the center bearing doesn't "load up" like you say.


From photos (as I haven't crawled under my car to look), it appears the bonded section is in the front part.


Also, steel is used because it's the most durable and won't work harden. Carbon fiber is outside the price point this car was aimed at. Carbon driveshafts are very strong, have a high critical speed, and when they do fail, they just become a broom. Downside to them is that rock chips can easily weaken them.

Bottom line. You're arguing something that doesn't matter since you haven't looked at it. The effect is what I was trying to get across. I wasn't insinuating that it loads like a CF shaft but you can definitely feel it "clunk... clunk" for lack of a better term as power is applied and removed. The joint is suspended near the support bearing and rubber so it does load even though the joint itself is tight.

[Pete156]

Originally Posted by stugray

So as I said - removing 1 pound from the driveshaft is the SAME as removing one pound from anywhere else on the car.

Are you saying that removing unsprung weight from a car has the same effect on performance and acceleration as removing sprung weight? The driveshaft is unsprung weight!


Removing 1kg of unsprung weight is equal to removing 6kg of sprung weight. So as you said........................huh?

[Pete156]

Originally Posted by stugray

Point out where I am wrong and then explain where I can find an explanation where I am wrong.
Physics is on my side (something I excel at).

So as I said - removing 1 pound from the driveshaft is the SAME as removing one pound from anywhere else on the car.

I am fairly certain you are wrong. I have an aluminum driveshaft. Do you really think that if we have identical stock 86s, and I put the aluminum driveshaft on one and you take 12 lbs off the other (from sprung weight) that the cars would run the 1/4 mile equally over lets say ten consecutive runs? I believe physics would be on MY side.
I am all ears.

[stugray]

Originally Posted by Pete156

Are you saying that removing unsprung weight from a car has the same effect on performance and acceleration as removing sprung weight? The driveshaft is unsprung weight!


Removing 1kg of unsprung weight is equal to removing 6kg of sprung weight. So as you said........................huh?

Maybe you should learn the terms before you try to argue with someone.
The Driveshaft is NOT unsprung weight.

Originally Posted by Pete156

I am fairly certain you are wrong. I have an aluminum driveshaft. Do you really think that if we have identical stock 86s, and I put the aluminum driveshaft on one and you take 12 lbs off the other (from sprung weight) that the cars would run the 1/4 mile equally over lets say ten consecutive runs? I believe physics would be on MY side.
I am all ears.

Yes. But be my guest and and run the tests.

And in a drag race, "sprung" versus "unsprung" means the least compared to any other kind of race.

[industrial]

I'd just like to point out that the science of physics and the engineers involved in the design of automobiles universally agree that lighter driver shafts are beneficial to performance cars as long as their strength is not compromised. This is hard science. There is no arguement here.

What Stugray is arguing is a completely subjective opinion on whether he thinks a mod is worth it after reading internet articles.

This forum is fucking ridiculous sometimes.