Bob and list,

K&N makes a specific filter for the 2.1l Vanagon WBX and a specific
filter for the 1.9l Vanagon WBX.  The shape of each of these filters is
exactly the same as the stock filter.  The filter for the 2.1 is about
$35 to 45 in most instances, while the filter for 1.9l is more
expensive.   Cost me slightly over $51 at a store that sold me the 2.1l
filter for $37.

Each filter simply replaces the stock filter in the stock filter box.
 The Syncro would be no more or less capable of fording any particular
body of water due to the presence of a K&N standard filter as all
standard air intake "hardware" remains in place.

Sam Walters