Air-intake System.. Fuel Saver?

Just installed an air-intake system... claimed to improve around 30% of mileage (heheh, doubtful? me too. kekeke). The kit costs RM180. What the heck, just give it a try. It was not a desperate move, but a kamcheng move to support the one who recommended me the system mah! Will report later if this thing works or not.