"Dan Luke" wrote:
Anyhow, one of the best tips I picked up from John Frank was to cruise my
engine more over-square than I usually do, i.e., instead of 26"/2400 RPM or
25"/2300 RPM, run it 27"/2200 RPM or 26"/2100 RPM.

In general, I recommend running at the highest MP and lowest RPM
combination in the engine manufacturer's power setting table for the %HP
you want to achieve. This will give you the lowest noise, lowest
vibration, and best efficiency.

On top of that, the tach runs slower too, so if you're paying by tach time,
you save money. If you're a commercial operator watching the hours tick
down to an obligatory engine overhaul or inspection, it's good for you too.