Dual induction system for internal combustion engine having splayed intake passages

A multicylinder reciprocating internal combustion engine with a dual induction system, with said engine comprising:

• a cylinder head having at least one exhaust poppet valve and a single intake poppet valve for each cylinder, with the intake valve being located so as to control the flow of charge into the cylinder;
• a plurality of rocker arms, with each having a first end in contact with the stem of one of said poppet valves, and a second end in contact with a linear drive member extending between the rocker arm and a camshaft driven member;
• a plurality of intake ports for conducting fresh charge to each intake valve, with each of said ports extending through said cylinder head and having a vertical wall dividing the port into primary and secondary passages, with the primary passage being oriented so as to cause rotational flow about the outermost portion of the cylinder, and the secondary passage being oriented so as to cause flow directed about a radially inward portion of the cylinder, with each of said walls having a passage therethrough for allowing one of said linear drive members to extend through the cylinder head, and with said primary and secondary passages being splayed vertically into separate planes so as to allow clearance for a secondary throttle shaft external to the primary passages;
• and
• a plurality of secondary throttle valves, with one such valve being located within each of said secondary passages upon a common secondary throttle shaft extending through said secondary passages, but not through said primary passages, for selectively controlling the flow through said secondary passages.

A multicylinder reciprocating internal combustion engine with a dual induction system, with said engine comprising:

• a cylinder head having at least one exhaust poppet valve and a single intake poppet valve for each cylinder, with the intake valve being located so as to control the flow of charge into the cylinder;
• a combustion chamber defined by the heads of the exhaust valve and the intake valve, as well as by a relatively flat piston top, and further by the cylinder head roof, which is generally wedge shaped;
• a plurality of rocker arms, with each having a first end in contact with the stem of one of said poppet valves, and a second end in contact with a pushrod extending between the rocker arm and a tappet;
• a plurality of intake ports for conducting fresh charge to each intake valve, with each of said ports extending through said cylinder head and having a vertical wall dividing the port into primary and secondary passages, with the primary passage being oriented so as to cause rotational flow about the outermost portion of the cylinder, and the secondary passage being oriented so as to cause flow directed about a radially inward portion of the cylinder, with each of said walls having a passage therethrough for allowing one of said pushrods to extend through the cylinder head, and with said secondary passages being splayed vertically above said primary passages so as to allow clearance for a secondary throttle shaft external to and above the primary passages;
• and
• a plurality of secondary throttle valves, with one such valve being located within each of said secondary passages upon a common secondary throttle shaft extending through said secondary passages and above said primary passages, for selectively controlling the flow through said secondary passages.