Moveable aperture for alteration of intake manifold cross sectional area

A device for the passive variation of an air fluid stream entering an engine comprising:

• a body having an exterior wall and an interior wall said interior wall defining an interior cavity;
• an intake aperture at a first end of said body;
• an outlet aperture at a second end of said body said outlet aperture having a center axis point;
• said interior cavity of said body communicating with said intake aperture and said outlet aperture defining a fluid stream passageway through said body;
• an outlet aperture area adjustment means whereby the area of said outlet aperture varies to produce desired fluid stream characteristics therethrough, said outlet aperture adjustment means comprising:
• an inward curve in the wall of said body at said second end of said body toward said center axis point of said outlet aperture;
• a plurality of slits in the wall of said body along said inward curve of said wall of said body, said slits defining flexible vanes;
• said vanes having a calculated bias towards the center axis point of said outlet aperture whereby the cross sectional area of said outlet aperture varies from a smaller area to a larger area to produce said desired fluid stream characteristics through said outlet aperture.