In a preferred embodiment, a spark-ignited internal combustion engine is provided with a valved receiver chamber connected with the combustion chamber adjacent the spark plug. The receiver valve is open at peak combustion pressures to admit combustion chamber gases which are retained in the receiver until discharged to the combustion chamber after ignition of the charge on the following cycle. The arrangement and method provide substantial combustion chamber charge dilution for limiting nitrogen oxide emissions without adversely affecting ignition of the air-fuel mixture.


diesel parts
import car europe