I do not claim to be an expert on aerodynamics.  Nor do I claim that the
scoops have any kind of performance boosting properties (sorry if I gave that
impression).  These particular scoops were actually developed by Winkler
(they don't look the same as the SA ones) when they started installing the
TDI engines into the Vanagon.  They found that the scoops gave them more air
flow for the intercoolers.  That is pretty much it.  So for a normal Vanagon
owner it would probably only be a cosmetic thing.  Do I think it would
actually hurt performance, I doubt that it would affect performance to a
noticable degree one way or the other.

The other thing I would like to say is that some folks have said that a scoop
would only be effective if the air was channeled directly from the scoop down
a tube and into the intake.  Well, having the advantage of owning a set of VW
of SA microfische, I would like to tell you that this is exactly how their
scoops are set up.  They have a molded piece of plastic on the inside of the
scoop that channels the air into a snokel that goes directly to the intake.
Does this aid in performance?  I dunno, but it probably helps keep water out
of the intake really well (you could do some serious wading with one of these
beasts).

So in conclusion, to scoop or not to scoop, it all depends on if you think
they look cool or not.

Ken Wilford
http://www.vanagain.com
John 3:16
Office (856)-765-1583
Shop (856)-327-0027
Fax   (856)-327-2242