here's the kit that makes the vents functional:
GBodyParts.com Online
someone asked 'how' they work, my .02:
I would imagine they work like those valve cover breather/evac systems that are attached to the exhaust via a rubber hose. The exhaust (travel direction) pulls the air out of the engine thru the breathers.
so when the car is moving, the wind draft around the body 'sucks' (or pulls) the air out of the engine compartment thru the design of the louvers, since the louver outlets are facing the rear of the car.
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