Hi, I was wondering if it was better to run the heater hoses directly to the intake manifold and water pump, deleting the hose to the radiator? Or is it best to keep the hoses connected to the heater valve and to the radiator? Which is best and is there really a noticeable difference? Thx again!!!

 

The supply hose should come from somewhere on the engine. The return hose can go to either.

When the engine is still warming up, you would like to start getting heat in the car as soon as possible. Once the coolant has gone through the heater core it can be returned to the engine to be reheated quicker or returned to the rad to go through the entire system again. Until the engine is at operating temperature, most of the coolant is recirculated through the engine with only a little bit bypassed to the rad. Once the thermostat is opened, it all goes through the rad to maintain a constant temperature.

The intake manifold should be the hot side and the waterpump or rad is the cold side.

 

Okay...so which line is the supply side...the inside or outside pipe on the firewall?