Cylinder head

Abstract

A cylinder head (1) disclosed herein includes a cylinder head main body (10) having an intake port (3) communicating with a combustion chamber (2) of an engine; and an insulation member (20) being arranged at an inner side of the intake port (3), made of resin, and formed into an annular shape. A step part (14) is formed at a downstream side of the insulation member (20) in a flow direction of intake air in the intake port (3) such that the intake port (3) has a cross section perpendicular to the flow direction at the downstream side smaller than a cross section perpendicular to the flow direction at an upstream side of the flow direction; and an annular seal member (21) that seals a space between the insulation member (20) and the step part (14) is arranged between the insulation member (20) and the step part (14).

Dependencies are inferred from the claim text.