http://www.google.com.au/search?sour...trol+injection
Due to the way direct injection works atomisation is no longer an issue compaired to port injection which where alot of torque has been gained, the stratergy with 2 ports per cyl was to try and create earlier response and torque which is not a strong point of earlier turbo engines.
Although im sure the shutter valves do exactly what they are designed to do they fail, what I mean by fail is that the same result can be seen by removing them and port matching to remove the problems in flow in the port runners. Air flow, air speed and temperature is all effected and soon I hope to have the flow results of my cylider head so these things can be seen. The inlet will no doubt have an effect to these readings. It food for thought.