Intake system for multiple cylinder engines

Claim 1

In an internal combustion engine having a cylinder head forming at least in part a combustion chamber, a cylinder head induction passage extending through one side of said cylinder head and terminating in an intake valve seat, an intake valve supported for reciprocation by said cylinder head for controlling the flow to said combustion chamber through said induction passage, a wall extending through a portion of the length of said induction passage for dividing said passage into two portions, the cross-sectional area of each of said portions in planes perpendicular to the direction of flow through said induction passage being substantially greater than the cross-sectional area of said wall in said planes, said wall terminating at a spaced location from said valve seat to define an area disposed adjacent said valve seat where said portions may freely communicate with each other, a valve body affixed to said one side of the cylinder head and having a passage aligned with the induction passage of said cylinder head, said valve body being formed with a wall aligned with the cylinder head wall and dividing the passage of the valve body into two portions aligned with the respective portions of the cylinder head induction passage, a throttle valve supported in one of said portions for controlling the flow therethrough, and the portion of flow to said combustion chamber through said portions, said throttle valve means being effective to substantially preclude flow through said one portion for a substantial portion of the idle, low speed running condition for supply of the engine charge requirement substantially through the other of said portions during such running conditions, an intake manifold affixed to said valve body and having a runner defining a passage having its outlet end mating with said valve body passage, and a wall extending from said outlet end at least partially through said runner for dividing said intake manifold passage into two parts, said manifold wall being aligned with said valve body wall, and charge forming means for delivering a fuel air charge to said intake manifold and through said valve body and said cylinder head induction passage to said chamber.