Don't use automotive mufflers.
Make your own out out of Inconel or 321 Stainless.
Best not to put anything inside that can melt
and plug up the exit.  This one has been sawed
off. Not a good idea for anybody on the ground
that might happen to be under it when it spits
out its guts.

----------------------------------
This is a fail safe muffler. If the ribs melt
and distort they are unlikely to plug up the exit
and can be inspected by merely looking under the
airplane.

Paul Lamar




Paul, that was on a plane at Oshkosh, that had another muffler forward of
that exit diffuser. I don't believe this is failsafe, depending on what the
forward muffler consisted of, because anything coming loose would be trapped
by the exit bars.

These were added on to the original design, and the builders said that it
reduced the sound some more, therefore they liked it.
Bill Schertz
KIS Cruiser #4045
N343BS
Phase I testing

Absolutely true but I also advocate putting nothing in the muffler ahead
of it.

Paul Lamar