An intake manifold is for a marine engine having a throttle for controlling flow of intake air to the marine engine. The intake manifold has a plenum for receiving the intake air from the throttle, a plurality of intake runners which extends from upstream ends for receiving the intake air from the plenum to downstream ends for discharging the intake air to the marine engine, and a quarter wave resonator extending from an open end coupled to the plenum to a closed end, the quarter wave resonator having a tuned elongated cavity configured to attenuate sound emanating from the marine engine via the plurality of intake runners.

A hydrogen intake assembly for a hydrogen internal combustion engine characterized in that the hydrogen intake assembly includes at least one air intake manifold comprising an air intake pipe comprising at least one air inlet and air outlets, air intake runners comprising air inlets and air outlets, a spacer having a wall defining an inner chamber receiving a mixture of air, water and hydrogen and comprising air inlets and mixture outlets delivering said mixture, a water rail comprising at least one water inlet and water outlets, said water outlets being embedded in the wall of the spacer and a hydrogen rail comprising at least a hydrogen inlet and hydrogen outlets.

A snowmobile includes an engine including an engine head including a cylinder head, a supercharger, an intake manifold, throttle bodies, first joints that connect the intake manifold to the throttle bodies, second joints that connect the throttle bodies to the cylinder head, and a restrictor that connects the engine head to the first joints. The restrictor includes an engaging member that fits into grooves of the first joints, and connectors that connect the engaging member and the engine head to each other. A steering shaft is inserted between two mutually adjacent first joints which have a distance from each other greater than a distance between the other two mutually adjacent first joints.

An intake assembly for an internal-combustion engine includes an intake duct for each cylinder, which communicates with an airbox that includes a filtering element. Each intake duct communicates with the airbox by a respective throttle body. A monitoring channel connects the intake ducts together and is configured for perturbing in a negligible way the dynamics of the fluid inside the intake ducts. Associated to said monitoring duct are sensors for monitoring the pressure inside the monitoring duct and designed to send signals indicating the value of pressure of the fluid taken in by the engine to an electronic control unit.

Methods and systems are provided for introducing a charge motion to a cylinder via a protrusion system coupled to an intake port of an engine. In one example, a system may include positioning a tongue from inside a spring-loaded casing to extend into air intake runner, generating desired tumble and swirl along an intake port proximate to an engine cylinder.

An intake manifold is provided having a base plate with discharge ports and an elongate pipe section extending along a face of the base plate. The pipe section has a front end with an intake port and progressively narrows at least adjacent a rear end. A first port in the rear end enables back-flushing of the manifold, and a second port in the rear end is angled relative to the base plate and enables insertion of a probe. Fork-lift openings extend between the base plate and the pipe section enabling the manifold to be lifted and positioned with a lift truck. Side ports extend through the pipe section and are angled relative to the base plate and adjacent one of the discharge ports to enable visual inspection of the discharge port. The side ports may include side ports located on both sides of the pipe section.

Methods and systems are provided for introducing a charge motion to a cylinder via a bladder in an intake manifold runner. In one example, a system may include positioning a bladder in an intake port proximate to a cylinder.

This air intake apparatus is mounted on an in-line multi-cylinder engine, and includes a surge tank that includes a throttle body mounting portion at a central portion thereof, one air intake pipe, which is single, and the other air intake pipe, which is single, connected to one end and the other end of the surge tank in a left-right direction, respectively, a first air intake pipe group that is connected to the one air intake pipe and includes a plurality of branched air intake pipes, and a second air intake pipe group that is connected to the other air intake pipe and includes the same number of branched air intake pipes as the plurality of branched air intake pipes.

An intake manifold is provided and includes a runner that is connected between a plenum and a cylinder head to allow air introduced into the plenum to enter the cylinder head. A dent is formed at the runner such that the dent extends along a channel of the runner while having an inner surface with a protruding shape. The runner has, at an end thereof, an inner surface formed to be flat without being formed with the dent. The inner surface of the runner is connected to the cylinder head.

Charge air coolers (CACs) are commonly used in pressure-charged, internal combustion engines to reduce the temperature of the air entering the combustion chamber. Typically, one CAC is provided and all of the intake air is inducted past the one CAC. An intake manifold in which a plurality of CACs are provided in the intake runners, i.e., a parallel flow arrangement, is disclosed herein. By positioning the CACs in the intake runners, the CACs are more effective than when they are positioned upstream in the plenum. In some embodiments, the coolant is supplied and returned to the multiple CACs via headers. By providing coolant to each CAC that is substantially the same temperature, the cylinder-to-cylinder temperature variation is reduced compared to a single CAC.