I will offer you some advise if you want the fastest motors on the market for 8 scale or 10 scale these are the motors you want.
10 scale
#1 jp eagle tl3-t
#2 murnan modified 353
#3 nova max xxl3
# 4 murnan modified rb r3
8 scale
#1 jp eagle r9
#2 Murnan modified 35+21
#3 359 tuned or murnan modified
If you have the money to spend go with the jp eagle line of motors for either class they are the fastest motors on the market no matter what the other racers say they are wrong when tuned right they have more top end then any other motor on the market but i will tell you murnan modifieds have the most low end and mid range of any motor with crazy top end just a little less than the jp.