[Lou Speed]

There are other interesting features in those special valves. They enable using cam profiles that would not be reasonable with conventional intake valves. The open times may be extended because the valve is actually a reed valve. A reed valve will be actually closed when the pressure in the combustion chamber exceeds the pressure in the intake port. It would be enough that the intake valve is completely shut during ignition and expansion (power stroke). The intake valve could open slowly during the exhaust stroke and close slowly during the compression stroke. The accelerations of such intake valve would be smaller than accelerations of a conventional valve with conventional cam profile. With a conventional intake valve this kind of slow and gentle cam profile would be plain ridiculous and the engine would not work. But these valves are not conventional. Also, because these intake valve may be full open during the intake stroke, that will improve also flow and peak power at high speed.