From what I found and was directed towards lg motorsports makes a carbon fiber shaft.
Direct vette replacement was $1,300, so, I'd need a longer custom one. And then I'd still need to extend the housing for the shaft on top of that. So, I'm looking at probably around 2g's I'd guess for something that would hopefully hold up, and if it ever fails will cost an arm and a leg to replace and take who only knows how long to get.
I haven't really found anything better yet but so far its sounding less appealing from a durability standpoint.

Don. what do the vette guys do for stronger torque tubes?!?!?!?!?!?! im not talking the D/S inside the tube But the tube/housing itself.

Dte makes a brace but i think thats it. Otherwise they switch to a real ds i think

They switch to a regular shaft? Didn't know there was stuff to do that if that's what they do. That would solve all my issues.

I could be wrong since i don'town one but with all the different trans swaps they must unless i am mistaken

Sorry just looked it up they change the shaft inside the tt not the whole tube :(

Yeah been searching around myself for the past couple hours and all I can find is the driveshaft shop makes an upgraded internal shaft to whatever length you want out of stronger aluminum, or a carbon fiber shaft.
From what I'm seeing there is no upgrade for the outer tube itself. Just braces to stop it from flexing.
While it would be great to keep the vette stuff I'm starting to question if it's worth it from a durability/cost standpoint.

Ok, so I took some half ass measurements this afternoon and it looks like I'd have to recess the firewall about 6" to keep the stock tube length. Doesn't look like it would work out so well that way since I still need room for my feet ;)
So, guess I need to decide if I want to trust custom stuff or just say screw it and stick with a live axle. Hmm...

Whatever way you go, it sounds like its going to be a tough project. You'll probably want to figure out which way you are going sooner than later because changing your mind would probably get expensive.

There's a few different types of turn racing. Autocross, track days, and road racing are all somewhat different from each other. If you are serious about one of these or another type.. just realize that how competitive you are rarely has to do with your setup. Especially if you have no experience. Once people get experience, then tweaking the setup becomes more important. Someone who's had no seat time usually isn't very competitive in the best setup car on the course. Another thing is in some cases you realize that you were worrying about the wrong kinds of modifications and some modifications actually hurt your performance and handling.. or they help but just bump you up to a harder classification.

I'm guessing for your case, I would solely do this for the "cool factor". If you want to take it to some track days or autocrossing, no doubt will you get a lot of compliments even at events that are dedicated to other cars like the BMW or Porsche club autocross events. If you want to be competitive, its usually a whole different path that you need to take that people don't really understand until they get some seat time under their belt. Doing it for fun is always fine, but most people who do it for a year or two typically don't want to keep on just doing the event for fun and not be competitive. Thus I would try to figure out whether you think the time and money you spend on setting the car up will be worth the time you think you'll spend using it for what you built it for.

That's just my .02. I don't want to see anyone spend a lot of money on something and find out it didn't really help. I'm at the opposite extreme.. I stick with stock classes and like to be competitive in them because they are cheaper cost wise and I'm also not a huge fan of working on my car every week

Yeah that's kinda where I'm at. Trying to decide if it's worth it.

From a coolness factor hell yeah. But, coolness won't make it work any better. Just trying to decide what will be best for me. I keep waffling on the rear choice. I do however need to make up my mind soon though.

On another note, called the drive shaft shop today. They make stronger aluminum shafts to go inside the torque tube and will make it any length I want for an extra $50. So that puts me about $950 for a shaft then all I should have to do is have the tube itself lengthened. Which shouldn't be too big of a deal to have done locally.

So, hmm, is it worth all the effort for a rear mount transaxle and IRS over a conventional trans and live axle. Funny thing is with what I have here for parts even with lengthening the tube and shaft it would probably cost me a grand less than a solid rear/link style suspension. Hmmm....

In all honestly I'll most likely never race the car competitively. I don't have the time or the finances. It'll just be for my own fun on the street and the once in a blue moon track day