carbon fiber exhaust

[basanti]

Ideally how thick should the carbon fiber sleeve be for a DIY exhaust project?

[ace.cafe]

There should be an inner liner of sheet metal like aluminum inside the carbon fiber tube. The carbon fiber epoxy binding matrix cannot handle the heat of the exhaust directly. The carbon fiber tube will turn gray and look like an ash color if the epoxy binding matrix is overheated. There are some special carbon fiber products used with a high-temp epoxy binder, but most of the tubes you see for consumer use are not. Even at best, they can only handle 500 degrees F for the high-temp ones, and the regular ones can barely take 300 F.

[basanti]

You mean exhausts like Akrapovic and Yoshimura have a metal sheet under the carbon fiber? Yet its so light! Is the carbon fiber bound to  the metal sheet during its forming/curing? Or are they two separate pieces?  How thin a stainless steel sheet would be used? 

I read else where that you can use epoxy resin and after curing it at room temperature to cure it in an oven at around 200-250 C for 2-3 hours and it would with stand higher temperatures much better and could be used for exhaust. But it didn't say whether there was a metal sheet under it or not.

[barenekd]

Understand that exhaust temps exceed 1100 degrees.
Bare

[ace.cafe]

I don't know what Akropovic use, but I would guess they make their own carbon fiber tubes with the high temp resins.
I seriously doubt a carbon fiber tube from Ebay is going to hold up to exhaust temps.

If I were doing it, I'd make an inner muffler can inside it, with some fiberglass insulation(no paper) in between the inner can and the carbon fiber. It wouldn't surprise me to find that's what these companies do.

[basanti]

Cool, thanks Ace.