I have an oil pressure problem with the 318 I just built, it has 15-20 psi max at 2000 rpm and falls near 0 at idle, it also has very little oil flowing to the rockers and the lifters won't pump up so it's not the gauge. The strange part is I can drive the pump with a drill at 1300rpm and get 50psi with plenty of oil to the rockers.

The oil pump is a M72 Melling, all the galley plugs are in place, it has clevite 77 bearings, full groove on the mains, standard rods, clearance it .0016" on the mains, .001" on the rods.