> >> Hi,
     > >>
     > >> In his book ?Firewall Forward?, Tony Bingellis
     > >> describes a Swiss
     > >> Muffler. Have anyone tried it on a rotary. I?m
     > >> thinking of using it on
     > >> my Vision to offset some of the weight of the
     > 13B.
     > >>
     > >> Regards,
     > >>
     > >> Pierre
     > >>
     > >>
     > >> Its been tried several times on the rotary. The
     > >> rotary chews it up and
     > >> spits it out.
     > >>
     > >>
     > >> Paul Lamar ...No rotor no motor.
     > >
     > >
     > >
     > > I might try one downstream of my Hushpower
     > muffler,
     > > depending on how quiet the hushpower ends up
     > being. As
     > > it was with just the hushpower, the engine is not
     > too
     > > loud.
     > >
     > > Brian Trubee
     > >
     > > This is a cheap muffler that works well on the
     > rotary because
     > > of the formed steel case. There are no drastic
     > section changes that tend
     > > to fail. It is also stream lined somewhat so it
     > does not add a lot of
     > > drag.
     > >
     > > Paul Lamar ...No rotor no motor.
     >
     >
     > Paul,
     >
     > That isn't the Flowmaster I was thinking about, I
     > didn't know they made one
     > like that.  How much does it weigh?
     >
     > Steve
     >
     > I don't know. I think Brian has one. What does it
     > weigh Brian?
     > --
     > Paul Lamar ...No rotor no motor.

    I can't give you a weight because it is installed.
    Also, I've welded the 'Y' collector onto it, along
    with the O2 sensor. the dimensions are:23"
    overall,(19" for the body, the inlet and outlet pipes
    add 4") 5 1/2"wide, 3 1/2" deep.  It's made out of
    some sort of stainless steel, I forget which series,
    but Tracy reports that it holds up well.

    Brian



    Paul,

    We have been thru the rotary muffler issues as well as other users
    in your
    group. We looked at the Hushpower online and were considering trying
    it. Do
    you have any input to this muffler as far as temps it will withstand and
    constant power, noise level Etc? We would be using this in a hovercraft
    application running 5500 to 6000 max RPM with our single engine.

    Any input would be appreciated.

    Eric Barger, President
    Phone 419-694-3000 x 222
    RotaMax Inc.
    15152 Twp Rd 190
    Arlington, OH 45814
    Fax 419-694-1401
    www.rotamax.net <http://www.rotamax.net>

    I don't have any hard data on it as I have never heard the engine
    run with
    one on it without a prop. Typically the prop is half the noise or
    so. I am
    just guessing. At 30 feet off to the side of the airplane with a
    prop it
    is about 103 db plus or minus 3 as a wild ass guess.

    It is cheap enough so give it a try. It seems to work for us.

    What sort of fuel burn are you seeing at 5500 to 6000 RPM in terms
    of gallons
    per hour?

    Paul Lamar ...No rotor no motor.


Eric,
I heard a Renesis run at high power with the Hush Power II muffler.  It
was very, very quiet.  Most of the sound was coming off the prop.
Reportedly, the neighbors have commented that his airplane is the
quietest one on the field.  This is a Renesis (side-exhaust port) engine
which is running a cut down cast iron exhaust manifold, and a small (4"
dia.) tangential muffler in addition to the Hush Power II.  So, your
results may vary.

The downside of the Hush Power II is that it weighs about 10# (my
estimate).  Even so, I'm considering installing one on my 20B.

Mark S.

By way of explanation the Renesis RX8 engine is a side exhaust port which is
much quieter all on its own. Eric's engine is a peripheral exhaust port engine.

So Mark I take it the spiral in the exhaust down pipe was not totally
satisfactory as far as noise is concerned?  Is it still in there?

BTW How many hours do you have now? How is your fuel injection working?