Help me understand the specs on a neumotor.

[Kiwi]

Thanks,
I'm going to convert a Muggy.
I plan to race, my local track is an indoor hard packed clay, my brushless AE B4 had an average speed of 10mph in my very best race. I don't want top end, it needs to hit 25 or 30 mph in about 4 feet of runway, plus braking is very important to me so I'm going to incorporate mechanical brakes, because I need front/rear bias adjustment.

So I'm considering a 1521 1y motor. (1577Kv)

any suggestions?