Hey,  maybe you can try this- put an exhaust splitter/turnout so that you
can use  the muffler, and if
it craps out on you, you can just open the exhaust  turnout and use
unmuffled exhaust to get back on
the ground. It would also  be an interesting exercise in how much power you
could make un-muffled.
You could also use it when  landing  at remote airstrips to  chase the
wildlife away from the runway.
Brian Trubee


Or make the bypass spring loaded so that a blockage would  overpower the
spring and open the valve.

Lynn E. Hanover