Provided is an intake manifold for an internal combustion engine, the intake manifold including an upstream portion, a first downstream portion, and a second downstream portion. The upstream portion includes a first upstream passage and a second upstream passage. The first downstream portion includes a first downstream passage configured to communicate the first upstream passage with an intake port of a first cylinder head. The second downstream portion includes a second downstream passage configured to communicate the second upstream passage with an intake port of a second cylinder head. The upstream portion, the first downstream portion, and the second downstream portion are provided in a separate manner. In the intake manifold, a flange of the first downstream portion is connected to a flange of the upstream portion, and a flange of the second downstream portion is connected to the flange of the upstream portion.

Provided is an intake manifold for an internal combustion engine, the intake manifold including an upstream portion, a first downstream portion, and a second downstream portion. The upstream portion includes a first upstream passage and a second upstream passage. The first downstream portion includes a first downstream passage configured to communicate the first upstream passage with an intake port of a first cylinder head. The second downstream portion includes a second downstream passage configured to communicate the second upstream passage with an intake port of a second cylinder head. The upstream portion, the first downstream portion, and the second downstream portion are provided in a separate manner. In the intake manifold, a flange of the first downstream portion is connected to a flange of the upstream portion, and a flange of the second downstream portion is connected to the flange of the upstream portion.

An air intake device includes: an air intake valve provided so as to change intake air by rotation of a rotation shaft; an actuator which is a driving source for rotating and driving the rotation shaft of the air intake valve; a first link member rotatable by a predetermined operation angle about the rotation shaft; a second link member rotatably connected to the first link member; a connection member which connects the first link member and the second link member so as to be rotatable to each other; and a biasing member whose one side end is engaged to the first link member and whose other side end is engaged to the second link member or the connection member to bias the first link member and the second link member or the connection member so that rattling between the first link member and the second link member is suppressed.

To provide an intake system of an internal combustion engine that can improve rigidity of a throttle body by strengthening a connection between plural components having an intake passage and further stabilize the opening degree of the throttle body. An intake system of an internal combustion engine includes: a plurality of throttle body members, each having at least one intake passage; and a plurality of structural connectors that are provided on respective throttle body members and connect adjacent the throttle body members with each other. The plurality of structural connectors includes a pair of structural connectors that are connected with each other in directions different from each other.

To provide an intake system of an internal combustion engine that can improve rigidity of a throttle body by strengthening a connection between plural components having an intake passage and further stabilize the opening degree of the throttle body. An intake system of an internal combustion engine includes: a plurality of throttle body members, each having at least one intake passage; and a plurality of structural connectors that are provided on respective throttle body members and connect adjacent the throttle body members with each other. The plurality of structural connectors includes a pair of structural connectors that are connected with each other in directions different from each other.

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 intake manifold includes a surge tank and left and right intake pipes. On a part of an outer periphery portion of the surge tank that faces a front direction or a rear direction of a vehicle, a pressure measurement portion to measure pressure in the surge tank is provided. A pressure sensor is attached to the pressure measurement portion. A sensing space containing one end side that is opened in the surge tank and the other end side in which a pressure sensing portion of the pressure sensor is disposed is formed on the pressure measurement portion. A bottom surface constituting the sensing space of the pressure measurement portion is inclined downwardly toward an opening portion to the surge tank.

An intake manifold includes a surge tank and left and right intake pipes containing one end sides each connected to the surge tank, and respectively extending to both side directions of the surge tank. A gas distribution passage portion to distribute exhaust gas to each of the left and right intake pipes is provided along a lower surface side of the surge tank and lower surface sides of the left and right intake pipes. An exhaust gas inlet and a gas distribution passage connected to the exhaust gas inlet are formed on the gas distribution passage portion. A communication hole to communicate an inside of each of the intake pipes and the gas distribution passage is formed on each of the left and right intake pipes.

A vehicular engine comprises a crankcase in which a crankshaft is operably disposed and by which a plurality of pistons translate within cylinder blocks operatively coupled to the crankcase. This vehicular engine may have interchangeable cylinder blocks and exhaust manifolds, a balancer shaft disposed below the crankshaft, a balancer gear separably coupled to the crankshaft to engage a front gear of the balancer shaft and supply lubricant to the crank shaft, a separable insert disposed within the crankcase proximal to a con rod of one of the plurality of pistons to supply lubricant thereto, or combinations thereof.

A vehicular engine comprises a crankcase in which a crankshaft is operably disposed and by which a plurality of pistons translate within cylinder blocks operatively coupled to the crankcase. This vehicular engine may have interchangeable cylinder blocks and exhaust manifolds, a balancer shaft disposed below the crankshaft, a balancer gear separably coupled to the crankshaft to engage a front gear of the balancer shaft and supply lubricant to the crank shaft, a separable insert disposed within the crankcase proximal to a con rod of one of the plurality of pistons to supply lubricant thereto, or combinations thereof.