The A3 plug and Tower's muffler turns the .46NT into a strong engine. It has noticeably more power than a .46FX.

The model I inherited from a friend went from barely hovering with his .46FX to hovering with spare power to pull out with the Evolution.

W8YE is right about the APC 12.25x3.75 prop. It is a stump puller for the Evo.

You are going to get big rpm bumps with those two items. Your model is a bit heavy though for hover power with a .46 engine.