Today was the first day I've really flown my ultimate in ambiant temps above 60 degrees F (it was in the mid 80's today). Anyhow, the YS 63 kept on overheating......and it deffinatly wasn't due to a lean run. It's got to be the lack of airflow over the engine. I haven't done anything to the cowl other than cut the holes for the exhaust and head of the engine to exit.

i'm thinking I should probably expand the inlet holes..... but what about where the air exits???? Is the slot at the bottom/end of the cowl enough for hot air to escape??


Im thinking that with the engine mounted inverted, there would have been signifigantly better cooling..... (but looks suffer)

WHat do you guys think??