"Some say too much vacuum will pull oil away from the wrist pins, rod and main bearings." Never thought of the repo's on that vac suck... makes sense if I think concave, pressure up against, for every action. So from under the piston, I can see something going on here with exhaust air pressure, looking under a piston, not some plumping plug. Then add turbo to mix and dry as a bone under there is not enough time if at ATMO lets it hang around with more at the strokes.