The 16-valve engine's cylinder block has several modifications to help make it more suitable to the higher power output, primarily in the lubrication system. The passageways between the crankcase and the upper cylinder head are larger, to allow better ventilation and oil return, and an additional oil passage in the block supplies oil to a series of spray nozzles, one below each cylinder. At oil pressure above 3.5 bar (50 psi), the nozzles open and small streams of oil are sprayed at the underside of each piston to provide additional cooling. The cylinder block casting is also modified to accept a larger crank-case breather.