Have any of you guys who run extended periods of full throttle ever experimented with reduced spark lead time as a method of reducing heat. 28 degrees is usually too much if the squish band is tight enough to do any good. I know that ignition timing and CHT are directly related on larger displacement cylinders, with heat climbing much faster than power once full rpm is reached. I reduced the spark lead to 19 degrees on my G62 for starting purposes, it cost 100rpm at 6100. I don't know if it made any temperature difference but I have since ran this new engine leaned to peak (and then some) for over 30 minutes, over-propped, with no sign of distress.