there are some monster sized motors on hobbycity. i'm most likey going to use a kb45 series motor. i've seen people get tons of torque with the L motors. the XL motors are just SICK! a feigao xl motor is 36x74 while a kb xl is 45x78. the only downside is you will need to either find a 30mm spaced motor mount or make one with 30mm spacing for the mount screws.