Get you some 30% fuel. You will get a good increase in power and your engine will actually run cooler since you will have to open the needle valve for more fuel flow. This is why your heli fuel is 30%. They benefit from more power and cooler running engines. Helis do not get the good airflow that fixed wing craft benefit from. If you are running 4 stroke you will not have a problem. On the 2 strokers you want to listen for any detonation. If you do have detonation it is a simple fix of adding an additional head gasket which will lower the compression a tad. I am pretty sure you can then do your hovering thing without having heat problems and also pick up quite a bit of power. This is your simplest and cheapest fix for heat and power. Good luck.