Dennis,

 

Are you climbing with WOT or do you throttle back to 24 inches?  I am at 55 feet here so my NA take off with ram effect can get to around 30.5.  I usually fly with WOT and control the engine power (and cooling) with the MT prop.  I dial it back to around 6K for climb after I reach a safe altitude.

 

Your EGTs are similar to mine, maybe a little lower.  My exhaust would not be considered quiet.  I had a Hushpower II on it but became concerned that I might get an exhaust stoppage, so I just recently removed it an installed a 4” dia DNA muffler.  The sound is very similar.  Maybe a little louder, but I don’t know for sure.  I tried to get a loudness record before I changed the muffler, but the decibel meter I was using only went to 105 DB and that was not even close to what the level was.  :>(

 

I originally had a Performance prop on the plane with your same dimensions (76 X 88), but I could not get more than 5350 static rpm with it.  I was afraid I would not be able to get airborne with no more HP than that, so when the opportunity to get the MT prop at a “bargain” popped up, I jumped on it!

 

When you say you go lean of peak, what does it peak at?  How many degrees lower do you go?  20 inches would mean you are at about 8500 ft with WOT?  What does your rpm run at under those conditions?  I assume leaning drops your rpm?  From what rpm to what rpm?

 

I am trying to get some understanding on the “how to” for leaning the rotary.  I hope you and others as well chime in with their thoughts as well.  I know Tracy has economical running down to a science!   :>)

 

Bill