Re: Aluminum exhaust tubes, why not?
 

I would think the reason people don't use it is because it's harder to bend, I have never tried to run any thru my pipe bender but I suspect it would be prone to collapsing or cracking and most exhaust shop's are not capable of doing mandrel bends.

Oh and we don't run mufflers on racecars, lol

Re: Aluminum exhaust tubes, why not?
 

In the sixties we made some hedders out of a flange kit and "flex-a-tube" bendable aluminum tailpipe in about an hour on a 57 chev and picked up 3mph. No collector. Warren Johnson looked at it and wished us luck.

Re: Aluminum exhaust tubes, why not?
 

Did it sound like a Duesenburg?

Re: Aluminum exhaust tubes, why not?
 

Not meaning to shoehorn into this class again, I was confused as to what this tech forum was specific too, so forgive the rant.
I'll interject with one small note, thin gauge Aluminum tubing is readily available from any good stocked speed shop in many sizes ranging from 2" all the way up to 5" along with many sections which are already mandrel bent. Straight sections are also available of course.
I was just wondering because so many people have to run exhaust systems in other classes and with so many noise restrictions nowadays, Aluminum for the system along with the Mufflers may be attractive to some. The Turbo guys use them for many applications on their hair dryer combos. What puzzled me was; is there an exhaust flow hampering with its heat being evaporated before it reaches the end of the system?
Maybe it's a cost issue.

Re: Aluminum exhaust tubes, why not?
 

I've wondered if the collector could be made of aluminum? It might last on a drag car.

Re: Aluminum exhaust tubes, why not?
 

Mine did!

I'm always messing with jetting and after a couple of years running TTI step headers with collectors and jetting it as best as I could, I switched to a 3" exhaust with an X-pipe and ending at the rear housing with Dynomax Ultraflow mufflers. The extra 60+ lbs was removed from elsewhere in the car and it wanted jetting 1-2 numbers less. But in the end, I picked up .05-.10. I believe it was mainly the X-pipe.

If I didn't think it helped, it wouldn't have stayed on. It's cramped to swap center sections and the exhaust has to be dropped for trans swaps or disconnected for teardown.

It scared the heck out of me for a while because I heard things I never heard before!

Re: Aluminum exhaust tubes, why not?
 

I would have to question the headers. An H pipe between the headers might have had a similar effect, but I have a problem thinking the headers were correct. I have had some pretty long collectors in the past on my old Jr Stockers. Like 24" extensions on one PG car. Total of 36". Can't tell you how many people told me it was wrong. Wrong headers and too poor to buy more at the time. LOL

Re: Aluminum exhaust tubes, why not?
 

An Aluminum collector might not survive the heat source from the primary header tubes that's blasting only a few inches behind. The rest of the tubing doesn't see actual flame but a respectable amount of heat.