The guys with straight pipes (even with a lot of 90 degree turns) think they work GREAT! Their hearing went bad shortly after they started flying them : )
Tracy (waiting on some 2 1/4" pipe to hook up the Hushpower II muffler) Weight (9 lbs) is about 4 pounds less than my Spintech
----- Original Message -----
From: Russell Duffy
Sent: Sunday, February 15, 2004 12:57 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] muffler?
Greetings,
I'm working on mounting this 14 pound Spin Tech muffler, and just have to ask a question...
I know that rotaries are painfully loud with no exhaust on them. I also know that the cast manifold alone will help significantly, and that a turbo will reduce the noise to about normal Lycoming levels. As I understand it, this is partly due to the fact that there are twists and turns that the exhaust has to negotiate, which reduces the speed, and eliminates the supersonic pulses.
As it turns out, my primary pipes will have to make three 90 degree turns before they get to the collector. I've started wondering if these three turns are enough to reduce the noise to an acceptable level. My gut feeling is that it won't be enough, but I think some people are already running with little to no muffling. I sure would like to eliminate that muffler, but I'm not optimistic that it will be possible. What do you think? Silly idea?
Cheers,
Rusty