Paul Yaw wrote:

Aagh!  A Supertrapp is about the worst thing that you can bolt to an
exhaust pipe.  It belongs in the scrap pile along with a flowmaster
muffler.  I personally would rather have both my balls hammered flat
than run a Supertrapp on one of my motors.  A better choice if you want
to build something is to build a simple absorption style muffler with
stainless steel wool packing.  It will be quieter, and offer almost no
flow restriction.  A Supertrapp on the other hand will create a huge
amount of exhaust backpressure which will limit horsepower and increase
BSFC.  I have used just about every muffler available at one time or
another, and have had several on the flowbench.  I can not say enough
bad things about the Supertrapp.  Anything that restrictive should at
least be quiet, but they are VERY loud.   If I understood correctly,
this is for a piston engine.  With the lesser temperatures involved you
might be very happy with a Borla XR-1, or Dynomax Ultraflow.  I do not
have a URL for either of these companies, but I would imagine that they
are both on the net.

Paul Yaw

 
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