Robert Linton

Although the CGT is very complete and, by far, the best of the current generation of supercars, perhaps a carbon fiber/aluminum/titanium drive shaft might be an interesting addition.

Jack Ennuste

It is, thats for sure!

AeroGT3RedWing

If it would last, it sure would be.
But it won't.
Carbon fibre is great in compresion and tension, but not in shear although its torsional rigidity is great.
Shearing stresses are at their peak in torsional shafts like drive shafts.
Mazda's are tearing CF shafts apart, with less than 200 bhp.
The carrera GT will eat them up.

Robert Linton

With all respect, these have been tested to in excess of 400,000 cycles from 0 to 3000 Nm of torque (far, far more torque than the CGT) and there was no issue. In fact, the only fatigued components after such tests were the metal ones.

P.S. Another highly stressed carbon fiber component.

AeroGT3RedWing

Wow. That's impressive.
Bravo.

qirex

its kinda wierd that nissan could put a CF driveshaft in the 350Z, but porsche didnt?

i'm sure that the engineers at weissach know better than us.

btw, the only real advantage of CF in the DS is for driver safety!
not weight, not strength - just to avoid cutting/flailing a driver to death in the event of DS failure.

DJ

Could someone please clue me in, because I'm obviously clueless...

I know that front-engined, rear-drive cars have driveshafts--to transmit the power from the front to the rear. I thought that the Carrera GT was a rear-mid-engine design, utilizing a transaxle... where is the drive shaft?

FSAEracer03

Wouldn't that depend on the direction of the weave? True, CF can't withstand shear forces and bending moments for squat, but those can be translated to normal stresses with varied weave angles and such.

The issue I'd me more concerned about is driveability. They already have incredible low rotating inertia, a problem that factored into the 1st reported CGT accident (5 min. after delivery!).

DJ, some refer to half-shafts as drive-shafts.

The main advantage to CF components isn't safety, sorry. Lowering the rotating mass the engine has to spin allows for quicker revving and less powertrain loss. It's the same as using a lighter flywheel.

DJ

Thanks, Kevin.

"some refer to half-shafts as drive-shafts"



"Calling things by their proper names is the beginning of wisdom."
- Confucious

M Danger

what are those parts for/from??

that rear arm looks like an old trailing type design, why would anyone use that?

qirex

I guess you're right. I should have specified its simply one of tyhe adnatges not the only one.

http://www.acpt.com/article4.html

johnfm

Mike

those 'old' composite trailing arms are for Rob Linton's 964 project. If you search thru the 964 posts you will find than Robert and his colleagues have re-manufactures nearly all the components of the 964 to this standard. It is truly amazing engineering. But not cheap!!

FSAEracer03

Robert, just out of curiousity, where are those half-shafts from (what car) and how much do they weigh? If you guys went all out with the calculations and compared your CF axles to steel ones with respect to rotational inertia and polar moment of interia, PLEASE share! If no one else is interested, my PM box always is

...I'm an engineer, can you tell? lol

EDIT... I really need to read over what I post before I post it... or take some typing class, haha.