CRT.5 Bruushless 1:12th ompetition indoor truggy

I want to remove my nitro engine and re-install a brushless in mine too, but i've a feigao 8s can, and i think to buy a 7.4v 3700mAh flightpower li-po, but not certain about a 7.4 volts setup in this truck.
Is i'll get a good power and good runtime I've always had 3s or 4s system, don't know anymore about 2s setup.