On a cowl hood ('72 SS clone) there is that piece in the vacuum hose I beleive the term is Flow Control Valve? It was missing on my car so I just purchased one but it can be installed either way. Is there a correct way? Curious about its function as I can blow thru it both direcetions, is it just a $20 restrictor? Or?

Dave,

It is a restrictor. It should slow the opening and closing action on the outer flapper door. Typically, the metal side is toward the vacuum source, and the black side is facing the vacuum pod on the door. If this doesn't work, flip it over. There have been a bunch of people that have purchased valves that function as a check valve, and the door won't work with those. It sounds like you have the correct part if you can draw air through in both directions.

Dave

Dave
Thanks
Dave
OBTW I saw your link to your car, looks a lot like mine
Red 72 454, pretty complete SS clone, near perfect low miles no rust car with 18" wheels, Corvette 13" brakes, bench seat and about to get white stripes,




Dave,

It is a restrictor. It should slow the opening and closing action on the outer flapper door. Typically, the metal side is toward the vacuum source, and the black side is facing the vacuum pod on the door. If this doesn't work, flip it over. There have been a bunch of people that have purchased valves that function as a check valve, and the door won't work with those. It sounds like you have the correct part if you can draw air through in both directions.

Dave