I'm seeing about 1.4 to 1.5 GPH at idle, around 700-800 RPM. Aux fuel pump on increases it by about 0.1 GPH. Idle is perfect and smooth - no problems at all.
However, this seems a bit lean, based on some calculations I've done which might be wrong. I just used max FF max HP and max RPM for my io-360 and by reducing the RPM I reduce the HP, which of course should reduce the FF.
Down around 600 RPM my calcs show that I should be at about 40HP and 3.3 GPH. I'm sure there is something obvious that I don't understand, but not clear what. Perhaps since the engine is not under any load, the HP requirements are of course far lower than 40, and this would reduce the FF requirement? But the engine is pumping air...and I guess it needs the correct ratio of fuel to burn? Or perhaps the mass of air flowing is a lot lower, even though the volume could potentially support 40HP?
The original reason for looking at this was to ensure that I was leaning properly on the ground. FF at takeoff on my last flight was about 16.3 at 2500 RPM, which I think is right on target.
I have a Mattituck IO-360, 8.5:1, Superior Cold Air Sump, AFP FM-200, dual pmags, auto plugs BR8ES. Everything is working perfectly, just trying to understand this a bit better.
However, this seems a bit lean, based on some calculations I've done which might be wrong. I just used max FF max HP and max RPM for my io-360 and by reducing the RPM I reduce the HP, which of course should reduce the FF.
Down around 600 RPM my calcs show that I should be at about 40HP and 3.3 GPH. I'm sure there is something obvious that I don't understand, but not clear what. Perhaps since the engine is not under any load, the HP requirements are of course far lower than 40, and this would reduce the FF requirement? But the engine is pumping air...and I guess it needs the correct ratio of fuel to burn? Or perhaps the mass of air flowing is a lot lower, even though the volume could potentially support 40HP?
The original reason for looking at this was to ensure that I was leaning properly on the ground. FF at takeoff on my last flight was about 16.3 at 2500 RPM, which I think is right on target.
I have a Mattituck IO-360, 8.5:1, Superior Cold Air Sump, AFP FM-200, dual pmags, auto plugs BR8ES. Everything is working perfectly, just trying to understand this a bit better.