Originally Posted by DoubleVision
One runs from the water pump, the other runs to the coolant port on the front passengers side of the intake. The rear ports are meant for cross over cooling front to back often used on race cars and not needed on the street.
As for inlet and outlet that's easy, the size of the heater core outlets will tell you which is which as one is 5/8 and the other is 3/4.
3/4 goes to the water pump. 5/8 goes to the intake.
the only thing is im installing a heater in my car that feeds of the water system like regular heat does, and it has a inlet and outlet so i just wanted to no where i can run the 2 house i have to cut 2 5/8 holes in my fire wall to run the hoses from the inside of the car to the engine block
theres a pix of the heater