I forgot to mention late (zzzzzzz) last night that the specs I quoted
were for centrifugal advance only.  I also added below the spec for
vacuum advance which appears to be functioning normally.  My Haynes
manual tells me the distributor is not user serviceable and must be
replaced when faulty.  Is this so? Do I need to secure a replacement?
Can anyone forward a recommendation on a replacement and source?

My measurements:

           total adv     vacuum
           cent + vac    disconnected    specs*

 820rpm     7deg BTDC    7deg BTDC     7.5deg BTDC @  850rpm
2000rpm    38deg BTDC   26deg BTDC    9-14deg BTDC @ 1600rpm (cent only)
3000rpm   >50deg BTDC   38deg BTDC   21-25deg BTDC @ 3400rpm (cent only)
                                      8-12deg total vacuum advance

*as published on Old Volks Home website - Thanks!

Note the difference between the timing with vacuum disconnected and the
specs for the same.  Total vacuum advance falls within high end of spec.

Thanks for your assistance,

Tony

Anthony L. Mourkas
Hampden, Maine, USA
1981 Vanagon Westfalia (resting, awaiting surgery)