Bob,If that person is kamzkab86 on the Samba, I refer you to page 6 of that thread near the bottom with her post about the comparison of anemometer readings for the setup with the plenum in place, measured at the rear outlet and between the front seats at various fan settings, versus without the plenum for the same series of measurements. �Looks like a significant difference in measured airspeeds to me. �True, no mention of temp differences in that post but others in that thread have done temp tests.
Regardless, I'll keep going commando plenumwise. �I works for me and it's much more comfortable, so to speak.
Stephen

--- On Tue, 6/11/13, Robert Stevens <mtbiker62@GMAIL.COM> wrote:

From: Robert Stevens <mtbiker62@GMAIL.COM>
Subject: Re: AC Question
To: vanagon@GERRY.VANAGON.COM
Date: Tuesday, June 11, 2013, 7:51 PM

On Jun 11, 2013, at 5:02 PM, Stephen Grisanti <bike2vcu@YAHOO.COM> wrote:

No complaints, except for the rather unfinished look of that area now but that look is worth the improvement.
That Samba thread even has contributions by one owner who went so far as to do numerous measurements of airflow and temp for his/her van with and without the plenum.� That was a lot of work to prove a point.

I know the person/van who did that and reported about it. See her annually at one of our Van events/activities in May.
She reports that there was NO signaificant improvement in coolness OR air flow to the front. It resulted in "some"
additional head room for volks sitting in the rear bench.

bob