Jimt wrote 
never heard of adjusting valves on hydraulics

Fellow vanagon types 
There is not a day that goes by when I don't get a phone call about hydraulic lifters. http://www.bostonengine.com/articles/hydraulicll.htm They mostly come from those that have reinstalled the engine or rockers only to find they have low or no compression or low power. Most callers later tell me that the van never ran so strong. I think that popping off the valve cover twice a year to see the condition of the rockers, rocker clips, wave washers and to check the valve adjuster clearance is a good way to maintain your engine. I have been suggesting for some time that the preloading of hydraulic lifters causes low power poor hot starts low manifold vacuum and loss of power. I think its a good idea to adjust the lifters to 006th cold and then drive the van for a day or two then readjust them to 002 or 003th warm after the engine has cooled down enough to not burn the hell out of yourself.  
Loss or a gain in power in a vanagon is not easy to detect until you try maintaining speed as you climb a hill on the highway. I have just ordered a G tech Accelerometer http://www.gtechpro.com/  The owner of the chassis dyno I have been testing with suggested it and said it was an accurate and less expensive way to field test changes 

As for gas grades around town I don't see the need for high test but on the highway I won't run anything else. The problem is it is hard to predict what kind of driving I will be doing in the days ahead.
Bob Donalds 
as always
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