Advanced Composite Technology Products makes a nice C.F. driveshaft. (For a nice $900.+) but it is safer if it ever breaks, reduces vehicle weight and has much less rotating mass.
Just thought I'd post this as a general interest thing.

Since I'm new here I suppose it's already been posted many times.

 

https://www.rx7club.com/showthread.p...2A+drive+shaft

 

I would put that $900 into something else. The stock driveshaft is already pretty damn light.

 

nice link man

 

Accroding to my bible on 3rd gen development ("RX-7" by Yamaguchi & /Dinkle)
the designers wanted an aluminum driveshaft but it wqas nixed by the bean couynters at Mazda.
The RX-8 has a factory carbon fiber driveshaft and even some GM and Chevy trucks do also.
Anyhow, yes, my $900. first goes into a Crooked Willow double oil cooler system this winter then a Pettit intercooler, Walbro fuel pump and an Apex-i ECU & Controller and all the dyno testing that install entails to get it right.
Also, now that I've been enlightened here, I'm getting the 6 new rear suspension bushings too.

 

my mustang driveshaft is heavy as hell My FD needs something new.

 

How is it safer if it breaks?

 

It frays or "broomsticks" (the frayed end looks like a broom, hence the phrase), so it won't beat the car as badly or come through the floor pan.

 

...or catapult the car onto it's roof.