Those engines have to be set several clicks richer sometimes, than what you think
would be the correct setting. They heat up after running for a minute, and need a
richer setting to keep them cool.....they will lean out and start to sag.

If you lean one up to maximum RPM then keep richening the engine slowly
click by click, you will be surprised how many clicks it takes to get the engine
actually richened up when fully hot. I counted 12 clicks open from full peak on a
15 size engine on time....meaning I had to richen it up about 8 clicks from where
the owner had it set....the engine was dying out in flight, time after time.

When you set an engine that rich, sometimes it takes the engine a couple laps
to heat up and get back to where it was on a previous flight....but that's what it
takes in richness to keep the engine from overheating.

FBD.