An intake manifold made of resin includes a surge tank, a plurality of branch pipes branching off from the surge tank, an EGR gas distribution part for distributing EGR gas to each of the branch pipes, and an EGR cooler for cooling EGR gas introduced into the EGR gas distribution part. The EGR cooler and the EGR gas distribution part are made of resin and provided adjacently and integrally. The EGR cooler includes a gas passage through which EGR gas flows and a water passage through which engine cooling water flows to cool the gas passage to allow the EGR gas to pass through the EGR cooler and then flow in the EGR gas distribution part.

An outboard marine engine comprises a crankcase; a crankshaft disposed in the crankcase and being rotatable about a crankshaft axis; a crankcase cover on the crankcase, the crankcase cover enclosing the crankshaft in the crankcase; and an air intake plenum that is integrally formed with the crankcase cover. The air intake plenum conveys intake air for combustion in the outboard marine engine.

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.

The cylinder head includes: an intake port; a low-temperature cooling water channel for circulating low-temperature cooling water; a high-temperature cooling water channel for circulating cooling water of a higher temperature than the cooling water flowing through the low-temperature cooling water channel; and a gas channel for recirculating a portion of blow-by gas or EGR gas to the intake port. The low-temperature cooling water channel is configured to include a first water jacket that covers at least one portion of the wall surface of the intake port on an intake-air upstream side relative to an opening end opening at a wall surface of the intake port from the gas channel.

An internal combustion engine comprising: a plurality of cylinders; at least one intake manifold, which receives fresh air from the outside; a plurality of intake channels, each connecting a cylinder to the intake manifold; and an intake sound amplification device, which is provided with an amplification pipe, an insulating element sealing the amplification pipe in a tight manner, a plurality of amplification channels, each originating from a corresponding intake channel, and an amplification manifold, which, on one side, is connected to all amplification channels and, on the other side, is connected to the amplification pipe.

An engine system is provided. The engine system includes a rotatable intake port circumferentially surrounding at least a portion of a stem of an intake valve coupled to a cylinder, the rotatable intake port having a first curved section extending inward toward or outward from a rotational axis of the rotatable intake port. The engine system further includes an intake port actuator coupled to the rotatable intake port configured to rotate the rotatable intake port about the rotational axis based on engine operating conditions.

The invention relates to an air duct arrangement (100), in particular a charge air duct for a turbocharged engine, having an inlet air duct (60), a cooler (10) with an inlet (37) and an outlet (38), the cooler (10) having at least one air flow path portion (12, 14, 16, 18) extending between the inlet (37) and the outlet (38) along a longitudinal elongation (66) of the cooler (10) and having an outlet aperture (13, 15, 17, 19), and at least two runners (22, 24, 26, 28) of an air intake manifold (20) of an engine (40). The cooler (10) is arranged between the inlet air duct (60) and the runners (22, 24, 26, 28). Each runner (22, 24, 26, 28) has an inlet aperture (23, 25. 27, 29) and the outlet (38) of the cooler (10) is providing connection interfaces (73, 75, 77, 79) for the inlet apertures (23, 25. 27, 29) of the runners (22, 24, 26, 28).

An intake system of an engine includes an engine and an intake manifold. The intake manifold defines individual intake air passageways each connecting one of cylinders to a volume chamber. Each of the individual intake passageways includes a first route and a second route. The first route has a natural frequency, of an air column, synchronized with a first revolution higher than an engine revolution for maximum torque such that a dynamic supercharging effect is obtained at the first revolution. The second route has a natural frequency, of an air column, synchronized with a second revolution higher than the engine revolution for maximum torque such that a dynamic supercharging effect is obtained at the second revolution. The second revolution differs from the first revolution. A difference between the first and second revolutions is set lower than or equal to 15% of a maximum engine revolution.

A variable intake system includes first runners, each including a first inlet formed at one side thereof to introduce air from a surge tank thereinto, a first valve formed at the first inlet, and a first outlet formed at the other side thereof to discharge the introduced air, and second runners, each including a second inlet formed at one side thereof to introduce air from the surge tank thereinto, a second valve formed at the second inlet, and a second outlet formed at the other side thereof, wherein an extension part branched from the second runner is formed at the second runner, a third inlet is formed at the end of the extension part, and the total length of the second runner provided with the extension part is longer than the total length of the first runner.

An assembly for an internal combustion engine may include an intake module of a fresh air system for supplying fresh air to at least one combustion chamber of the internal combustion engine and an attachment part attached to the intake module in a joining direction. The intake module may include at least one retaining surface facing away from the attachment part. The attachment part may include at least one counter retaining surface facing away from the intake module. At least one reinforcing element may be disposed between the intake module and the attachment part and may interact with the at least one retaining surface and the at least one counter retaining surface. The at least one retaining element may be moveable in a movement direction extending transverse to the joining direction between a releasing position and a securing position.