Variable runner length intake manifold

A variable runner length air intake manifold for an internal combustion engine having air intake valve inlets, said manifold comprising:

• a housing having fixedly attached upper and lower halves, each of said plurality of runners having an equivalent cross-sectional area wherein each cross-sectional area has a different cross-sectional shape, said upper half including an air inlet portion and a plurality of air outlets, each of said plurality air outlets in communication with a corresponding one of the air intake valve inlets of said engine;
• a tapered drum having opposing ends disposed within said housing wherein one of said ends is open for receiving air from said air inlet portion and into said housing, said tapered drum operative to cooperate with said housing to form a plurality of runners, said tapered drum being rotatably mounted within said housing, said tapered drum further including a plurality of openings formed through an outer surface thereof wherein each of said plurality of openings is in fluid communication with a corresponding one of said plurality of runners whereby the air received through said open end passes through said plurality of openings and a portion of each of said runners into said air intake valve inlets of said engine defining an effective runner length for each of said runners;
• and
• a runner length adjuster in communication with said tapered drum and operative to rotatably adjust the position of said tapered drum within said housing such that said effective runner length for each of said plurality of runners is variable.

A variable runner length air intake manifold for an internal combustion engine having air intake valve inlets, said manifold comprising:

• a housing having fixedly attached upper and lower halves that define a plurality of runners, each of said plurality of runners having an equivalent cross-sectional area wherein each cross-sectional area has a different cross-sectional shape, said upper half including an air inlet portion and a plurality of air outlets, each of said plurality air outlets in communication with a corresponding one of the air intake valve inlets of said engine;
• a tapered drum having opposing ends disposed within said housing wherein one of said ends is open for receiving air from said air inlet portion and into said housing, said tapered drum being rotatably mounted within said housing;
• a plurality of sealing ribs formed on an outer surface of said tapered drum that are spaced apart between said opposing ends wherein said tapered drum includes a plurality of openings formed through said outer surface and disposed between adjacent sealing ribs wherein each of said plurality of openings is in fluid communication with a corresponding one of said plurality of runners whereby the air received through said open end passes through said plurality of openings and a portion of each of said runners into said air intake valve inlets of said engine defining an effective runner length for each of said runners;
• and
• a runner length adjuster in communication with said tapered drum and operative to rotatably adjust the position of said tapered drum within said housing such that said effective runner length for each of said plurality of runners is variable.