In a message dated 12/1/2004 10:12:42 AM Central Standard Time,
sqpilot@bellsouth.net writes:

<< Hi, Ed....funny you should mention that....I was just considering ordering
a
 Supertrapp disc muffler which sounds somewhat similar to what you are doing,
 with the exception that it just attaches to the rear of your pipe.  The one
 that I am interested in is the 3" diffuser disc unit, as seen on
 www.http://recerpartswholesale.com/supert2.htm   One of my concerns, however
 is how well it might hold up, as any parts/pieces of a failed unit would go
 through my prop (pusher configuration), effectively cutting my flight short
 and/or ruining my day.  Good luck with flight testing, etc.  Please keep us
 posted.  Paul Conner
  >>

I recommend ordering two extra sets of diffusers for the Super Trap. It will
kill the power, but does cut down the noise. When we ran at Charlotte Motor
Speedway we had to add on of those to get down to 105 dB. There is nothing to
absorb sound at that track. A NASCAR race must be amazing to hear. I think those
things started out as a spark arrestors for diesel trucks used in National
forests.

I think a conical shape in the exit would have been less of a drag than the
flat plate, but we never went back, so I didn't work on it anymore.

Lynn E. Hanover