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Re: Floor Vent
Posted: Wed Apr 20, 2016 6:12 pm
by David Dunn
audiocontr wrote:Would placing a scoop on the Webesto grill port (behind driver) force enough air in to benefit circulation? Little to no modification is required.
Opening the front door windows would yield more benefit.
GG has those lower vents, and they
do move the air through the cab... as long as there is a place for it to exit.
Re: Floor Vent
Posted: Wed Apr 20, 2016 11:34 pm
by Jimm391730
At speed (40mph and up) the flat front forces the oncoming air outwards as the truck moves through it - up, left, right, and down. So the sides and roof of the cab are mostly in a partial vacuum since the air can't change direction as fast as is needed to get around the corners and any openings there (like windows) allow air to be sucked out. Replacement air comes from all the other leaky portions of the truck, generally further back, so in comes the exhaust fumes.
Hence the placement of these vents at the front corners of the cab to catch the higher pressure air and direct it into the cab.
My W, with the separate hard cab, gets a wonderful breeze from the airflow over the cab, hitting the box, which forces the air down between the cab and box. Opening the rear window on the cab at speed is like letting in a hurricane, and that air has not had a chance to mix with exhaust yet.