I have been following this discussion list for the past month or so and 
have  noticed that a dominant topic is choice of oil and keeping 
engines running at the proper temperature. Recently I mounted a second 
(EMPI) oil cooler on the side of my 82 Westfalia. This amounted to an 
increase in 10-20 psi or 35-40psi at 60 mph (especially noticeable after 
long hauls through 
the mountains). One possibility for this increase is the additional half 
litre of oil 
that is added to the system (any ideas on this-there seems to be some 
debate whether too little or too much oil is beneficial for pressure)? 
The other possibility is that the engines for these models (which had a 
life span of only three and half years-before VW switched to water cooled) 
were/are severely overstressed 
for the incredibly small OEM cooler. In the case of my van, loose main 
bearings and a faulty oil pump have been ruled out, so insufficient 
cooling/plus the additional weight of the Westafalia package seem likley 
choices  for the engine running hot (by the way head temp never exceeds 
250f - idles 200- speed). 

At any rate I have moved the cooler from the side in order to have the 
van "safetied" for an Ontario licence (the van was bought in CAL) to above 
the transmission. This also keeps it away from fingers and trees. The only 
problem with this set up is that there is 
insufficient air in there and because the transmission gets hot it heats 
the fins of the cooler. So hitting the junk 
yards I managed to piece together a Subaru fan motor (extremely flat and 
excellent power) with a fan from a Renault 5. This was the only 
combination of fan and motor that would fit under there. With a switch 
mounted to the dash, I can now control oil temp (with a view to buying an 
oil thermostatic switch that comes on at 180f). This reults in increase 
oil pressure and power (overheating leads to loss of power).

If any one wants info on how to go about this procedure contact me. In 
the meantime, I am curious if anyone else has had any oil pressure/temp 
problems with the air cooled vanagons or if you have any ideas on what 
may be the original problem. 
Extra coolers seem to be rare on these vans (unlike busses). Regards - DC