Patent ID: 8166939

Claim:
A cylinder head comprising: a cam bearing recess defining a cam bearing surface; a generally planar cam bearing cap mounting surface extending outward from a first end of the cam bearing recess with an edge being defined between the first end of the cam bearing recess and the mounting surface; an axially extending drilled oil passage providing fluid communication between the cam bearing recess and an oil source, the oil passage intersecting the edge and including a first radial portion extending through the recess and a second radial portion extending through the mounting surface with the edge dividing the oil passage into the first and second radial portions; wherein the cam bearing recess includes a reduced axial thickness region at a base of the recess, the reduced axial thickness region having an axial thickness less than twice a diameter of the drilled oil passage; and wherein the first radial portion defines an oil groove in the cam bearing recess and the oil groove extends along the cam bearing surface from the edge and terminating at a point between the edge and the reduced axial thickness region of the base.