i think you missing the point heat sink is only for show it doesn`t do any good at all they only fit on a 540 motor that dont get to hot at all i run my car for over 30 mins with this motor and the motor just get little hot,great for what? people want speed not to go 20 miles the hour with the stock spur gear and pinion,by the way gpm propeller shaft fit better to the car than tamiya`s one and its lighter too,i just cant get the car to go to straight line,if you want speed go to lrp 9t v10 spec 4 motor its very cheap and fast almost 47.000 rpm.battery use a venom 3600 will do,esc novak tc2,21t pinion,58t spur gear with this specs i get over 60mph