crt.5 ,building and tunning for speed help

hi just bought a crt.5 , im making it brushless , i allready had a mamba 4600 out of my rustler vxl .. but im unsure of the gearing because of the heat isues , ive just ordered the bore reducer and a 11t pinion .( i geuss i should have got 12 t instead ). but is there a better motor i should get instead of the cm36 motor fitted .. im after the most powerfull motor with good top end , and off the line power ..
its being powered by maxamps 5000 11.1v lipo,s..

plus any other mods are worth doing
..thanks for any help