From Crane's web site:
"Do not use
synthetic oil during the break-in period. It is not recommended to use any type of
oil restrictors to the lifter galley, or use
windage trays, baffles,or plug any
oil return holes in the valley. Oil has a two-fold purpose, not only to lubricate, but to draw the heat away from whatever it comes in contact with. The cam needs oil splash from the crankcase, and oil run-back from the top of the engine to help draw the heat away. Without this oil flow, all the heat generated at the cam is transferred to the lifter, which can contribute to it's early demise."
Most of the oil pans used in our cars have very effective windage trays.