If you work with race engines you know that building flow bench rigging is a pain. Using a 3D printer for cylinder bore and port fitments can allow many variables to be tested in a short period of time. This is an example of a Nissan VQ V6 race head setup. By using all thread, nuts and a bottom plate, the head can be held by the cylinder rig alone. Also note the valve controller uses a 3D printed fork to move 2 valves during testing.