High compression type internal combustion engine

摘要

A high compression type internal combustion engine comprising a cylinder head having a flat inner wall, and a piston having a flat top face. The flat inner wall and the flat top face form a squish area therebetween. A recess having a lung-shaped cross-section is formed in the cylinder head. A shallow groove is formed on the flat inner wall of the cylinder head so as to extend from the intake valve to the recess. An exhaust valve is arranged on the bottom of the recess. The squish area comprises a first squish area portion and a second squish area portion. The first squish area portion has an area which is about four times the area of the second squish area portion. A spark plug is arranged in the recess at a position near the first squish area portion and remote from the second squish area portion.