> > > >Jerry Hey wrote:

 > > >>
 > > >>  I remember that fish tail mufflers did not hold up to the rotary's
 > > >>  heat and energy.  Does anyone recall their affect on performance?
 > > >>  If this restrictive termination of the 2 inch diameter exhaust pipes
 > > >>  did not harm performance, than I believe a 3" tangential muffler
 > > >>  without any restriction might perform very well.
 > > >>
 > > >>  Jerry

 > > >Those were too simple. They must be beefed up. You cannot merely
 > > >squish the end of the pipe and call it a true fish tail muffler :-)
 > > >
 > > >Paul Lamar

 > > I'm not planning on using a fish tail, but knowing its effect on
 > > performance would be very useful.   Jerry

 Hi Jerry,
     I probably played as much with the Fish Tail muffler as anyone.
 Actually as Paul points out they were not actually Fish Tail ends as they
 did not conform to the dimensional requirements for a true Fish Tail, in
 fact I decided to call them Squish Tails as that more accurately reflected
 their nature (as well as construction method).

   Initially, I could not get a Squish Tail to live longer than 5-10 minutes
 as the intense exhaust pulse from my turbo block exhaust apparently caused
 the metal to fatigue quickly and chucks of metal would be missing.  However,
 if there were any effects on performance they were too small to notice.  I
 have since used a heavier gauge wall metal and also perforated the exhaust
 tubes (2 of them 4 feet long) with  approx 250 holes which probably reduces
 the intensity of the exhaust wave somewhat before it reaches the end of the
 pipe that the Squish Tail is on.

  The Squish tail did however, have some effect on the intensity of the
 exhaust sound.  Even when I was using a 18" pipe rather than the 4 feet I
 now use, you could tell the difference between that and a straight pipe.
 Never had a sound meter to provide quantitative measures of the difference.

 So I now have approx 60 hours with the current Squish Tail set up and it
 appears to be holding up.
 However, they are not the final answer when it comes to quieting the Roaring
 Rotary, particularly the turbo block.  I think that Tracy's Spintech or
 perhaps the Tangential approach is more effective.
 FWIW

 Ed Anderson

Nothing stopping some one from using both a tangential muffler and a fish tail
on the end of a square exhaust pipe. BTW I see that RB Wagner has square SS
bends.

Paul Lamar

Exactly what I have been thinking.  I am going to start with the
tangential.  If that is not enough, the fish tail can be added or
even a Spin Tech.   Jerry

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