flyrotary@lancaironline.net Mailing List Archive

Mike,

I had the same impression of the DNA muffler. Then I remembered what Tracy said about big pipes being louder than smaller pipes. So, I ordered a tapered transition piece from Burns Stainless, bringing it down from 3" to 2 1/4". That helped reduce the noise considerably and I couldn't detect any reduction in hp. Or, you could spring for a pair of those $800 headsets, or you could do both.

Mark S.

On Sat, Sep 5, 2009 at 10:46 PM, Mike Wills <rv-4mike@cox.net> wrote:

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.

Mike Wills

RV-4 N144MW