Slides and expendable cores for high pressure die cast closed deck engine block

An expendable core for use in high pressure die casting a closed deck engine block, the core comprising an arcuate inner surface, an arcuate outer surface, an upper portion, a lower portion, a top surface and a bottom surface, a first side surface and a second side surface, and an aperture extending through the core from the inner surface to the outer surface in a horizontal direction through the upper portion;

• wherein the entire lower portion has a thickness greater than the upper portion, the difference in thickness defining a shelf portion, wherein the thickness of the lower portion is consistent from the shelf portion to the bottom surface, wherein the first side surface and the second side surface taper outwardly from the inner surface and intersect with the outer surface, and wherein the aperture is located above the shelf portion and is parallel to a top surface of the shelf portion.