I have no idea on what buggy you have, and I don't know the first thing about buggies... BUT, I had that motor (for 2 months... cooked itself), you are going to want to gear for about 45mph, as the fiegao's need a decent load on them to be efficient, and not rev high(which is the number one killer of those....things)
So gear for 45mph and you should be okay for a few months until the motor just dies on you. It will go like there is no tomorrow, powerful motor.
