Cylinder head configured for improved cooling performance and manufacturability

A cylinder head comprising:

• a cylinder head casting formed of a cast material and including a top deck having a top deck upper surface and a top deck cavity surface, a bottom deck having a bottom deck combustion surface and a bottom deck cavity surface, a coolant cavity formed between the top deck cavity surface and the bottom deck cavity surface, and a plurality of gas exchange conduits extending through the coolant cavity to the bottom deck;
• an igniter column defining a center axis, and extending from the top deck to the bottom deck, the igniter column including an upper section, and a necked-down lower section surrounded by the bottom deck cavity surface;
• and
• the igniter column including an outer heat-dissipation surface formed on the upper section and on the lower section, the outer heat-dissipation surface forming a continuously wetted wall of the coolant cavity both circumferentially around the center axis and axially from the top deck to the bottom deck;
• wherein the outer heat-dissipation surface is as-cast from the top deck to the bottom deck;
• wherein the igniter column includes an inner surface forming an igniter bore extending upwardly from a machined igniter seat, and the outer heat-dissipation surface extends radially inward of the inner surface at locations between the bottom deck cavity surface and the machined igniter seat;
• wherein the cylinder head casting further includes a concave transition surface connecting between the necked-down lower section and the bottom deck cavity surface and defining a uniform profile of rotation around the center axis;
• and
• wherein the bottom deck cavity surface defines a concave curvilinear profile, in at least one of a fore-aft vertical plane or an orthogonal vertical plane, originating at the concave transition surface and extending upwardly and radially outwardly from the concave transition surface.