> >  > > Back awhile ago Tracy was running a tangential muffler made

 >>  > from .035 SS as I recall. As I also recall it only failed
 >>  > in a couple of places after 650 hours. Right were the hot
 >>  > gases impinged on the can causing them to turn.
 >>  >
 >>  > Correct me if I am wrong Tracy.
 >>  >
 >>  > Therefore I suspect that only certain small parts of the
 >>  > muffler that cause the exhaust gases to turn need to be made
 >>  > from .065 or thicker SS and only those parts close to the
 >>  > engine where the temps are highest. The rest of the muffler could be
 >>  > made from .035 or maybe .049 SS to save weight.
 >>  > The rest of the parts probably cool down to below 1000 F rather
 >>  > rapidly.
 >>  >
 >>  > In this muffler 3D the square tubes coming out of the engine should
 >>  > probably be made from .065 SS while the can could be made
 >>  > from .049 and the down pipe .035 with reinforcements in
 >>  > the fish mouth flat areas.
 >>  >
 >>  > Paul Lamar
 >
 >>  Please note that my original muffler cracked open after only 25 hours.
 >>  I had very short headers (2 - 3") going straight into the muffler
 >>(I'd doubled
 >>  the .035 in the area where the exhaust hit). It cracked around
one of the
 >>  headers.
 >>  The point here, is that if you have relatively short stiff
headers between
 >>  engine and mufflers, you need slip joints or some other system
to allow for
 >>  thermal expansion/contraction. Reason Tracy's held up so well
is he had flex
 >>  piping isolating it from the engine.
 >>
 >>  Finn
 >
 >Thanks for the tip Finn. A square tube slip joint is possible.
 >I will try to add it to the drawing.
 >
 >Jerry is it possible to weld a short square tube around a steel
 >mandrill
 >to make it super accurate?
 >
 >Paul Lamar

 I'm not clear about what you have in mind.   Please send a sketch.   Jerry

OK will do soon. We need some telescopic SS square tubes
between the exhaust flange and the muffler for heat expansion.

Paul Lamar

In my previous response I was thinking about my own situation which
already has a muffler attached to round exhaust stubs.  Starting
from scratch you would just use the sq tubing. An expansion joint is
no problem providing slip fit SS  sq. tubing can be obtained.   Jerry

I don't think it can so it must be welded up. That I think might
be a problem.

Paul Lamar
 
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