On Sat, 08 Nov 2003 13:21:32 GMT, David Megginson
wrote:

(Rick Durden) writes:

Not necessarily so. It is perfectly okay to lean at 75% power, the
manual for your airplane has a fuel burn for 75% with lean mixture.

Quite right. That one surprised me as well.

I always simply just lean for peak RPM whenever climbing... or even
taking off, anymore. I don't think I can hurt my low compression
O-320 this way. Three years and well over 300 hours later since I
bought the plane and this leaning style seems to suit this engine
perfectly since I have no EGT/CHT guages. I do lean as agressively as
I can to keep the engine smooth once I've reached level cruise
altitude. My plugs stay clean, my fuel burn is spot-on what a 150hp
Cherokee ought to get too. If I don't lean to peak RPM in climbs, of
course the climb rate is lethargic, and it seems like all I'm doing is
wasting gas and loading up my plugs and crankcase oil with extra lead
ash.