> > 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
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