| 001 Inside The Honda Civic Type R Head
| In order to develop new pistons, JE uses a Romer Absolute arm and laser scanner to rapidly create a digital model of the cylinder head. This let's engineers know what the chamber shape is, the chamber volume, and the position of the valves and spark plug.
| In typical Honda fashion, the K20C1 head is an excellent casting, but it is radically different from the K20A. No valvetrain or intake/exhaust manifolds will interchange between the two. Even the water jackets are significantly revised.
| One of the most obvious visual changes is the elimination of traditional exhaust ports. The K20C1 (left) uses a "headifold," which has internal exhaust runners unlike the K20A (right) which has traditional exhaust ports.
| The single, exhaust port of the K20C1 makes bolting on a turbocharger a very simple affair and was likely done to simplify design of the new Civic Type R. It also has emissions benefits due to surrounding waterjackets providing exhaust cooling.
| The K20C1 is significantly wider than the K20A, and also has a radically different valvetrain setup, featuring single, beehive-style springs and VTEC only on the exhaust side.
| The K20C1 uses a powersports-style spark plug that is smaller than the traditional 14mm thread used on the K20A. One potential benefit from the move to a smaller plug is more material between the valve seats. This is likely to add more strength to that area of the head but may allow for the installation of even larger valves.
| Compared to the combustion chambers in the K20A, the K20C1's are shallower and flatter. The valve angles have also been changed.
| Here you can see the extra material between the valve seats and the smaller spark plug well in the K20C1.
| The K20C1 incorporates single, bee-hive style valve springs whereas the K20A utilized a dual-spring setup. According to Luke Wilson at 4 Piston Racing, the engine exhibits valve float at only 7,300rpm—low for a Honda.
| Inside The Honda Civic Type R Head K20C1 Intake Port
| The intake port on the K20C1 head no longer has a scallop for port fuel injection since the K20C1 exclusively relies on direct injection. The intake manifold flange is also angled slightly, whereas the K20A's is flat.