When I built my 1835 cc, single port VW engine, I did the late Bob Hoover's HVX mods to the oil system. These mods increase the oil flow to the right head to match the oil flow to the left side of the engine. A large percentage of cylinder head cooling is done with the oil, so this mod helps on the CHT's. VW did these changes in the Type 4 engine. The one drawback to this mod is the increase oil flow tends to decrease the oil pressure. I know all of my bearing clearances were correct and my hot oil pressure was running about 32 lbs. I wanted to increase the oil pressure to 38-40 lbs. The stock gasket for the oil pump is .004 thousand thick. Since the oil pump housing is aluminum and the gears are steel there is a different expansion rate. I went to a gasket made from .002 thick gasket material and when the oil pump housing and gears are hot have .0015 clearance between the gears and the cover plate. Now my hot oil pressure ( 185/190 degs) is 40/42 lbs with a 20 lb hot oil pressure at 900 rpm idle.
Bob Hoover's Blog: HVX MODS
Dan
Bob Hoover's Blog: HVX MODS
Dan
