What function does the vacuum actuator on the box serve? I need a box for a 66 Chevelle and Chevy did not use this actuator. It will only be used until aftermarket AC is added but that may take awhile. TIA
Thanks for looking. Here is the answer from Joe at classicoldsmobile.com It controls the flapper door for air recirculation vs outside air. Vacuum to both ports gives you 100% outside air. vacuum to the upper port gives you 20% outside/80% recirc air.
