Gauging Interest - Carbon Fiber driveshaft

[Huffer]

I am thinking about setting up talks with a manufacturer to make a carbon fiber driveshaft specifically for
BD/BG/BK and BE/BH models, auto and manual.

Benefits:
Less rotational mass = less weight, quicker response (accel + decel), better MPG, less NVH
Gains of over 5% are common due to the reduction of rotating mass.
Much safer in an accident, carbon fiber will shatter and "broom" out. Metal driveshafts can puncture the chassis (and injure you!)
Because there's less NVH, there's less overall wear and tear on the vehicle.
Rated for much higher HP than stock shaft, and far more durable.

This will be in the realm of $1000-1200 so please indicate your interest if you can handle this type of cost.

Development and testing will likely see this project stretch out for weeks, so you have been forewarned.

Depending on the company I choose, I may need a few test mules, which would obviously be entitled to a discount.

Summary:
Carbon Fiber driveshaft
Only downside is price
$1000-1200

[J-Rock!]

WOW,,, Thats freakin sweet :grin:

[Mr. Sociable]

If I were rich I would do this.



But I'm not. Good luck though!

[wagonofdoom]

dont aluminum shafts have the same characteristics....but just dont shatter...

[Huffer]

dont aluminum shafts have the same characteristics....but just dont shatter...

The CF shaft is proven to be more effective not only at weight reduction but also in terms of improved NVH absorbtion and also for higher HP figures. The item I'm looking at is rated for 1500hp...but I doubt anyone with a 2nd or 3rd gen is going to get that close.

Aluminum shafts would be possible too, but there's the possibility that it could shear off in a crash and launch the car - a CF one won't do that as they're vulnerable to a side puncture:


Despite safety hardware like shaft hoops and covers, a broken metal driveshaft can become a flailing bludgeon that beats up everything in its' path; severe injuries to the driver, extreme damage to the car, and even vaulting the car into the air can be the result. Carbon fiber minimizes these dire consequences.

Carbon fiber driveshafts are built for strength primarily to transfer torque and can be broken with a hard blow from the side. The result is that when a u-joint or yoke fails the carbon fiber composite begins to disintegrate when it contacts the chassis or driveshaft hoop. As the composite comes apart, the shaft simply turns into a bunch of loose carbon fibers. much like the end of a broom . In fact, in composite technology this failsafe state is called "brooming". Instead of tearing up the driver and shredding the chassis, the carbon fiber broom will probably just polish dirt and paint off the chassis.

[Reason]

If all the drive shafts are the same as the impreza than I may be interested.

[Huffer]

If all the drive shafts are the same as the impreza than I may be interested.

Not sure on this one.
I know the R180 6mt diff uses a shorter driveshaft - same as the 4EAT autos.

The autos use a shorter driveshaft.

[deadlydave]

If you get this made, I won't look at the RWD coupe when it comes out...I'll keep the Baja.

So, count me in, seriously.

[Airgne]

i have seen CFF driveshafts for all subaru 5 & 6 speeds. i will look to see if i can find it again.

[Airgne]

ok so it wasnt a CF driveshaft. it was a 3in one peice driveshaft.

[wagonofdoom]

Aluminum shafts would be possible too, but there's the possibility that it could shear off in a crash and launch the car - a CF one won't do that as they're vulnerable to a side puncture:

ok....if htat is a valid argument, 100% of vehicles on the road are undriveable

buy a few driveshaft loops and it wont let it fall

[Huffer]

ok....if htat is a valid argument, 100% of vehicles on the road are undriveable

buy a few driveshaft loops and it wont let it fall

I never said alloy wasn't an option, but I happen to think based on all the evidence regarding the manufacturing process AND the road test of CF driveshafts for the STi that the CF shaft is lighter, just as strong and much safer.

There's is nothing regarding driveability from a 2 piece steel shaft... if that's your argument then why do we modify? Or seek NON-STOCK wheels to put on cars?

This thread isn't a debate - I want to see who has the desire AND the money to get a custom CF driveshaft made for their car.

[wagonofdoom]

i have both, but i just cant see any solid numbers that justify a carbon over an alloy of some sorts be it ACTUAL weights, rotational weight loss to HP ratios etc etc etc

[chuckthefuk]

I do know that a legacy driveshaft is about 6" longer then a GD STi driveshaft. Not sure if this helps but I thought I'd throw it out there.

Theres a member on the forum "Dip" who is undergoing a EJ257 swap and he is having an aluminum shaft constructed with "legacy" length and "GD" front and rear connections. Approx $100 .. Chromoly is $250 and CF is approx $1500

So Huffers price quote is extremely good.

-Chuck