GoWesty provided the most in-depth explanation I have seen so far.
Nothing like the "simple" German engineering of a Vanagon!
http://www.gowesty.com/library_article.php?id=311

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
Mike S
Sent: Tuesday, April 08, 2008 4:33 PM
To: vanagon@GERRY.VANAGON.COM
Subject: Re: ventilators in front doors

At 04:02 PM 4/8/2008, Woody Halsey wrote...
>Here is another question: Where does the air that allegedly flows
>through the vents at the bottom corner of the from doors come from? I
>always thought those vents were somehow connected to the
>ventilation...

The air comes from inside the Vanagon - they are _exhaust_ vents. The
air ends up leaving through the gap near the hinge, a low pressure
area. If you open the door, you can see where it's open along the front
edge to let the air out.