Engine cylinder block with optimized stiffness

摘要

An integral cylinder block (20) is provided having features which enhance structural stiffness, thereby reducing noise emissions. The block (20) includes an upper portion (24) with cylinder bores (26) and a lower portion (22) forming at least a part of a crankcase (28). At the upper and lower portions of the block, the casing (40) has sculpted wall portions (42, 44) with a curved, undulated shape. At a side of the cylinder block (20), a closed oil cooler cavity (80) is formed. A wall (86) is provided to generally separate the oil cooler cavity (80) from the water jacket (34) defined within the block (20). An opening (88) is provided in the wall (86), which is distally located relative to a water pump outlet (90) that provides a flow of coolant into the cavity (80), thereby improving the flow direction of coolant across the oil cooler. Also, an opposite side of the cylinder block (20) includes a closed tappet cavity (60) to accommodate pushrods. The closed tappet cavity (60) is defined by a sculpted tappet cavity wall (62) that is integrally formed with the upper and lower portions (24, 22) of the block (20), improving block rigidity. <IMAGE>