Hello, i'm experiencing a strange phenomena when installing a YS 63S (that runs great in my other airplanes) in a new sukhoi (kyosho).
The engine runs fine on the ground with APC 13x6 on CP 20/20 at full throttle 10.750 rpm's (as in my other planes).
However when airborn the engine doesn't have it's usual punch when going full throttle.
Looked at all the usual suspects (fuel lines, tank pressure, glowplug etc..) but all are ok.

Could it be caused by the lack of airflow going through the cowl ? Mind you the engine isn't running hot at all, it's not lean at all, on the contrary it looks like it's going rich...

Any ideas ?