I would get the 2200KV Motor if you are running a E-MAXX,I have a TeknoNue 1515 1Y witch is the same as the Castle 2200KV Motor.I'm running 4S TrueRC 8000K 15C Lipo's geared 18/68 and the motor get's warm but not hot.The 2200KV Motor is going to be a good choice for a Monster Truck.