I'm still mystified by the widely different results builders are getting with the Hushpower.  Both my planes have them.  I have over 500 hours on the RV-4 muffler and it's still in good shape (minus the fiberglass which goes pretty fast). Even the Hushpower on the 20B is still OK after 90 hours.   Admittedly, i do spend a lot of time cruising around at low throttle but every takeoff & climb out is at WOT. 

Only news on the 20B testing is that I found my fuel flow calibration was off so it wasn't getting as good a fuel burn numbers as I thought.  Still in the same ball park as the Renesis at similar airspeeds.  At sea level it gets pretty hungry above 215 mph though.  There the numbers look like what you would expect of a Lyc. IO - 540.  

Tracy

Sent from my iPad

On May 16, 2012, at 8:03 AM, "Ed Anderson" <eanderson@carolina.rr.com> wrote:

Hi Brian,

 

I have flown with two Hushpower mufflers for the past 8 years.  So far no restrictions, although the non-metallic sound deadener has long departed.  Also by having one muffler per exhaust, it may suffer less of a beating.

 

YMMV

 

Ed

 

Edward L. Anderson
Anderson Electronic Enterprises LLC
305 Reefton Road
Weddington, NC 28104
http://www.andersonee.com
http://www.eicommander.com

From: bktrub@aol.com

Sent: Wednesday, May 16, 2012 12:25 AM

To: Rotary motors in aircraft

Subject: [FlyRotary] Re: High EGTs

And I am running a Hushpower, I run a bore scope up it today and the exit cone looked completely intact. No way to check out the entrance cone without taking the exhuast  system apart, which is possible but a PITA. Is a Hushpower considered restrictive?

 

Brian Trubee

-----Original Message-----
From: Bill Bradburry <bbradburry@bellsouth.net>
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Sent: Tue, May 15, 2012 8:38 pm
Subject: [FlyRotary] Re: High EGTs

Mark,

Now you have gotten me concerned!  I changed the muffler and that didn’t seem to have any effect on the EGTs, so I don’t think that is the cause, but I don’t want to damage any orings.  What were the temps you were seeing when the orings were damaged?

 

Bill

 

---

From: Rotary motors in aircraft [mailto:flyrotary@lancaironline.net] On Behalf Of Mark Steitle
Sent: Tuesday, May 15, 2012 10:18 PM
To: Rotary motors in aircraft
Subject: [FlyRotary] Re: High EGTs

 

Brian, 

 

I had high EGT's at one time.  Turns out it was due to an overly restrictive muffler.  The high EGT's damaged the o-rings resulting in an engine overhaul.  Could this possibly be at the root of your high EGT readings?

 

Mark S.

On Tue, May 15, 2012 at 8:51 PM, <bktrub@aol.com> wrote:

My engine is now running just the way it should, temps were 180 or lower on a 75 degree day, but my EGTs have always been high, really high- above 1800 almost all the time. I think it may be a calibration issue. My egt sensors are about 3 inches downstream of the exhaust ports, and I am using Tracy's EM2, calibrated at the stock settings. When the engine is stone cold, the egt's read about 230 degrees, which I assume is normal because the sensors are meant to operate at a much higher temperature. Any thoughts?

 

Brian Trubee