Mike,
Do you have a way to measure the backpressure ahead of the
muffler? Does the design of the muffler appear that it would cause a
restriction greater than you already had?
Did your map table change, or does it just run richer? What is
different about the map table at the stage point?
Bill B
From: Rotary motors in aircraft
[mailto:flyrotary@lancaironline.net] On
Behalf Of Mike Wills
Sent: Saturday, September 05, 2009
11:47 PM
To: Rotary
motors in aircraft
Subject: [FlyRotary] DNA muffler
Received my DNA muffler this past week and got it installed
and running. Havent flown it yet, but have done some taxi and full power
runups. So far I'm a little disappointed. It doesnt appear to be any quieter
than my home made muffler. I'll reserve judgement until I actually fly it, but
from the cockpit the noise level seems the same, and my buddy standing about 50
' away said he thought the noise level was the same.
One thing not the same - the muffler screwed up my
tuning. It appears to be considerably richer now all across the RPM range. And
the big bog at the staging point that took me so long to tune out is back with
a vengeance. Oddly, in spite of the tune issues it still appears to reach the
same static RPM as previously.
Looks like the solution for me is going to be the high
$ headset and the rest of the world is just going to have to live with it.