Patent ID: 8590511

Claim:
An intake passage structure for an internal combustion engine, said intake passage structure comprising: a cylinder head having an intake valve guide passage formed therein for receiving a stem of an intake valve, the cylinder head comprising an intake manifold portion having an intake passage formed therein and an injector attachment portion formed therein in communication with said intake passage, said injector attachment portion situated on an opposite side of the intake passage from the intake valve guide passage; wherein said engine comprises: a cylinder defining a cylinder center axis; a fuel injector having a tip end disposed in the injector attachment portion; said cylinder head having an intake valve disposed therein; and a throttle body operatively attached to said intake manifold portion of said cylinder head; wherein: a fuel delivery passage is formed in the intake manifold portion extending between the injector attachment portion and the intake passage; said throttle body is attached to said intake manifold portion at a point of attachment, and said throttle body has a hollow bore formed therethrough which defines an extending direction of said intake passage; said intake passage branches from said point of attachment of the throttle body to form a plurality of branch passages; the cylinder central axis is arranged substantially parallel to said extending direction of said intake passage; said injector tip end disposed in the injector attachment portion is oriented with an outlet thereof facing towards said intake valve of the cylinder head; and an upstream side of said intake passage is arranged offset relative to the injector attachment portion in a width direction of the internal combustion engine.