Patent ID: 8408178

Claim:
A firing deck for an engine crankcase, the firing deck comprising: a firing side surface; a coolant side surface opposite the firing side surface; a plurality of cylinder bores through the firing deck from the firing side surface to the coolant side surface, the cylinder bores forming a centerline defining an intake side of the firing deck and an exhaust side of the firing deck; a plurality of bosses through the firing deck from the firing side surface to the coolant side surface, and disposed around each cylinder bore; a plurality of anti-distortion projections disposed on the coolant side surface of the firing deck and providing the firing deck with a varied thickness, wherein the anti-distortion projections are disposed on both the intake side and the exhaust side of the firing deck, wherein each cylinder bore has four bosses disposed generally concentrically about the cylinder bore, and at least one anti-distortion projection is disposed between each boss.