P.S. I put a Saito 180 in the nose with a stock muffler. It took approximately 2.5 pounds of lead and a Higley monster nut to balance to specs.

It does not struggle. It screams. To get to scale speed I drop the 180 to quarter throttle and fall asleep.

I run 50/50 30% heli fuel and cool power M/V 15%.