I am trying to restore this heaterbox and I found the core has two holes in it. I ordered that...I traced all the vacuum lines on the heaterbox but there is one that was just hanging there with a plastic nipple in the hose....its close to the fan motor. Luckily all the diaphragm pods work and the fan motor is working..

When was the heater valve used on cars? I am looking in the manual and there really isn't a reference to it. I see two bolts on the Passenger side fenderwell and just assuming that the heater valve is placed there.

If I remember right (CRS) when you turn the A/C on the valve cuts off the water flow.

I also think that vacuum hose with the plastic nipple goes to the vacuum "tree" that provides vacuum to the power brakes.

on my 70 cuda theres a cable operated heatervalve on the passengerside inner fender,i need it to turn on and off the heat.also theres a vacuum hose that enters the engine bay from the interior,it goes to a nipple at the rear of the oem holley and also tees to the dual snorkel air cleaner pods.