Does anyone on the list have any real-life rotary experience with the DNA Gen II muffler (http://www.dnamufflers.com/DNA/main_DNA.html)?  It is an interesting design in that it has no packing material to burn out.  Instead, it utilizes ladder-rungs, which they call "internal sound diffusers", which resemble a chain of DNA down through the center of the muffler body, which is made of 304 SS.  Their web site claims that the racers use them with great success.  From speaking with a sales rep, they claim there the rotary crowd uses them too.  I'm considering purchasing one of their FULL THROTTLE COLLECTOR mufflers (P/N 1040), but thought I would check to see if anyone else has used this style muffler.  This muffler has a 3" inlet/outlet with a 4" body.  So it is compact enough to fit inside my cowl.  My exhaust header has a 3" swivel joint, so it should be a good fit. 

 

Mark S.