Apart from maybe some specialised models (ambulance perhaps?), the
only vanagons i know of that had extra stiffening in the walls and
also frame rails, were the 14" syncro with the "bad road package",
and the 16" syncro.

I'd say both of those models are in the running for the stiffest body
structure.

alistair

On 28-Dec-10, at 10:00 AM, Tom Buese wrote:

On Dec 28, 2010, at 10:42 AM, mark drillock wrote:

> That C pillar cross brace IS welded in, both hardtop and Westy.

Thanks for the clarification Mark. Then there is some torsional
strength added at the C pillar.
>
> As for the sunroof vans, those have MORE roof structure than
> standard roofs, a lot more. I'd say the sunroof is the strongest
> roof, followed by the the hardtop, Westy last.

The hardtop is probably the strongest, then the sunroof, then the
westy, which is why the cross bracing around the openings was added
to compensate for the hole cut in the "shear diaphram" that the solid
metal roof contains.
Consider the box sections around the openings to be transfer beams
that transfer the torsional loads around the opening instead of thru
it.  Rule of thumb in structural engineering is that for every joist
cut out for an opening, you must add 1 on each side of the opening.

In split window buses w/ sunroofs, double doors & walk thru,
stiffener panels were added below the floor to compensate for the
removal of the stiffeners above- I bet something like this was done
on Sunroof & westy models also, unless they were able to get the
needed moment resisting stiffness in the  body/roof  by thickening/
stiffening the pillars/roof floor w/o the panels below the floor?

YMMV,

Mr. BZ-