Given these conditions:
Modern shock absorbers have variable damping rates depending on where they
are in their travel.
The variable rate is controlled by an internal metering rod that passing
through an orifice and the diameter of the rod is different along it's
length, allowing more or less fluid to flow depending on where the shock is
in its travel.
On a Vanagon there are at least three different lengths of stock springs
available and additional after market springs of different length.
The length of the springs will determine where the shocks are in their
travel when at rest and how far (to what position) they will travel when in
use while driving.
Assuming that all the above is correct, I would expect that the
effectiveness and performance of the shocks would be at least partially
dependent on what set of springs they were being used with.  If the spring
height is wrong the shocks may not perform as the designer intended, damping
may vary at the wrong point in the travel, to early or to late, to give the
performance desired.  Given this, how do we know what make/model of shock is
right for a specific Vanagon?

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