Abstract: A cylinder head for internal combustion engines, particularly diesel engines with direct fuel injection, which has two inlet valves per cylinder each including spin-inducing means for producing spin flow about the longitudinal axis of the associated cylinder. Having regard to the direction of spin, the leading inlet valve is provided with an eccentric, crescent-shaped chamfer facing in the general direction of spin flow, and the trailing inlet valve includes flow blocking means for preventing combustion air from exiting the trailing inlet valve in a direction opposite to the direction of spin flow.

Abstract: A cast cylinder head for an internal-combustion engine, in which the charge cycle ducts have a fluctuating duct offset relative to the valve opening caused by the casting technique. Proximate the opening, the charge cycle ducts are provided with a machining allowance which increases toward the duct end and are machined there in a cutting manner so that the interior surface of the charge cycle ducts changes in each case without an offset into the valve opening. In order to achieve a simple tool guiding and nevertheless a machining which is advantageous to the flow, a compensating groove is arranged in the machining allowance of the charge cycle ducts which has a flat V-shaped cross-section and extends in the circumferential direction, specifically--relative to the flow direction--at least in the area of a convex course of the duct wall. The groove flanks have a convex cross-section and are curved to be as free of flow separations as possible.