what kind of cars are you talking about?
I will go out on a limb and assume he has a tc and an oval car or 1/12th. He said carbon fiber chassis and 2wd, so that is the basis of the assumption.
To the original poster; we were all new at one time, and most of us were also captured by the speed neediness of the cars. However I strongly suggest using slower motors to start with. You need to learn to drive the cars and feel setup changes before you try bigger motors. The money you save by braking less parts could be spent in the future for the bigger motors when you reach that level of driving. Also believe it or not, the average rc driver will go faster around a track with a slower motor.