> "But Simon, the rears are stiffer than the fronts because of the
> engine's weight!"- No, stiffness and height are not necessarily
> entwined.

May I remind you of the Vanagon's 50/50 front-to-rear weight distribution?
 Yes, there's an engine back there but the total weight pressing down on
the rear springs is same as the front.  Rear springs are stiffer to handle
more when the van is loaded.

>
> http://www.farrside.net/vanagon/windtests.jpg
>

Stock Vanagon CD (coefficient of drag): .44
Flat pop-top:  .45
Westfalia pop-top: .51   <--- that sucks
High-top: .40
Camper-back: .46 <---- still better than the Westfalia pop-top

Based on the picture my presumptions that carrying a flat, wide load, such
as a cargo box, in the top luggage would reduce turbulence thus decreasing
CD.  Putting a plastic lid on the rack that slightly bulges out would have
an even better effect and save fuel when on the road.  Project, anyone?
Any fiberglass masters out there?

Chris S.
'85 Wolfsburg Westy "Camel"
http://www.knology.net/~vw/dadada.jpg