Mailing List flyrotary@lancaironline.net Message #3173
From: Tommy James <twjames@healed.org>
Subject: RE: [FlyRotary] Re: EC2 in-flight timing adjustment.
Date: Sun, 21 Sep 2003 13:12:12 -0400
To: Rotary motors in aircraft <flyrotary@lancaironline.net>
Tracy,  More questions stirred up here...:0)
1.  Will best power timing be different than best economy?
2.  What would you guess the EGTs to be at best power mixture and 5000rpm
3.  Is 5-6 bars on the RWS mixture meter the best power range?
Thanks,
Tommy <><
 
 
 
 1.  Establish normal cruise and get the plane *perfectly* trimmed in zero turbulance air.
2.  Lean engine for best economy.  This is about 1525 - 1550 EGT on mine.  This varies with altitude & powersetting.
3.  Put EC2 in mode 8 and advance timing 1 step (1.875 degrees) and note change in rpm (a digital tach w/ <= 10 rpm resolution is a must).
4.  If you got an increase at step 3, repeat until there is no increase in rpm.
5.  Retard the timing 1 step.
 
Factors to keep in mind.  My cruise is typically at 17 - 18" MAP which is below the manifold pressure advance point (this point is adjustable in Mode 6).  The timing is advanced by 5.625 degrees more than nominal timing which is typically 20 - 23 deg BTDC at rpm > 3600. 
 
I think mine is advanced 1 or 2 steps from default setting.
 
Tracy
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