I think people are making a mistake here.  It is 180 degrees on the crank and 
90 degrees on the distributor.  Direction of rotation is unimportant.  Also the cam
lobes have a constant radius over their back end (away from the raised part of the 
lobe used to actuate the valve).  This means that the valve lash reading will be constant
for about 90 degrees either side of TDC (crank rotation) for the cylinder being adjusted.

A. Burczyk

> 
> Joel wrote:
> >>
> >>after #1 is adjusted you just turn the crank pulley backwards so that the
> >>rotor goes 90 degrees in the 'wrong' direction, and that's #2. then another
> >>90 degrees is #3, and another 90 degrees is #4.
> >>
> 
> What Joel said (backwrads) means counterclockwise.  The Bentley for 83-84
> vanagons has a mistake (at least my Bentley is wrong) about this. It says
> to turn the crank pulley 90 degress. More precisely it should be 90 degrees 
> counterclockwise. I think this applies to all aircoooled bus/bug engines.
> Oh, hydraulic lifters can (need to) be adjusted if they are repacked,
> as described in the Bentley manual.
> 
> David Kao
> 
>