After recording my fuel and oil burn rate now for 450 hours on my computer and on a manual data sheet I can report the following regarding our 340 motors:

My typical flight is 2300 rpm, under 2000 ft, leaned, with lots of take offs and landings a Catto 78x54 prop. These numbers are the same ( believe it or not true) with 26 inch Bush tires or 1500 Bauman Amphibs.

1) Fuel burn 6.98 gal per hour
2) Oil Burn .12 Qt per hour


Interstingly I also noted that between 2400 and 2000 RPM a 100 rpm reduction results in approx 40 min additional duration. Best Gary