rememebr that the back of the motor is the farthest from the radiator. So it's better to boost the cooling to there. Also, I wouldn't worry about that hose depleting your coolant presure. The heater hose is a far smaller daimeter than the radiator hose. I use an aluminium tube for most of my joining loop. This is to prevent the exgtractors melting the hose, which happened to me once.