need brushless setup

[q8-maxx]

hello there

I have e-maxx with novak 4.5 but it run hot with 12 & 72 its give me about 43-47 mph

now I look for better setup from here that run with 16 or 18 cell cooler and faster than my novak 4.5 :)

I would like to hit 50-55 mph

I know I have to buy MGM but I dont know which motor i have to buy ofcourse not look for neu motors because I need cheap motor like fiago

and dont know what I need else

dont warry my maxx will handle 50-55 mph :)