SPARK-IGNITION INTERNAL COMBUSTION ENGINE

摘要

A spark plug is located in a combustion chamber ?o a? to decrease the combustion time of the charge inducted into the combustion chamber. The charge is formed, before inducted into the combustion chamber, by mixing an air-fuel mixture and substantially inert gas such as exhaust gas so that the weight ratio of the fuel combusted in the combustion and the substantially inert gas falls within the range from 1:13.5 to 1:18.5 during normal engine operation.