A forced induction device for an internal combustion engine is provided, which includes a shaft, and a compressor wheel that is threadably mounted to the shaft, and a tool that is configured to engage one or more through bores in the compressor wheel to thread and unthread the compressor wheel onto and off of the shaft. The compressor wheel has a plurality of blades with leading edges that converge at an apex. The apex is aligned with a centerline of the shaft. The tool allows a technician to rotate the compressor wheel relative to the shaft to install or remove the compressor wheel from the shaft without applying any pressure to the blades of the compressor wheel. An associated assembly method is also provided.

An internal combustion engine (10) fitted with a carburetor (40) is provided with a fire-resistant cover member (62) having a front wall (65A) facing an air inlet port (44) of the carburetor, and a breather tube (60) having an inlet end (60A) connected to a crank chamber (28) of the internal combustion engine main body, and an outlet end (60B) supported by the cover member at a position located between the front wall and the carburetor.

A forced induction device for an internal combustion engine is provided, which includes a shaft, and a compressor wheel that is threadably mounted to the shaft, and a tool that is configured to engage one or more through bores in the compressor wheel to thread and unthread the compressor wheel onto and off of the shaft. The compressor wheel has a plurality of blades with leading edges that converge at an apex. The apex is aligned with a centerline of the shaft. The tool allows a technician to rotate the compressor wheel relative to the shaft to install or remove the compressor wheel from the shaft without applying any pressure to the blades of the compressor wheel. An associated assembly method is also provided.

An internal combustion engine (10) fitted with a carburetor (40) is provided with a fire-resistant cover member (62) having a front wall (65A) facing an air inlet port (44) of the carburetor, and a breather tube (60) having an inlet end (60A) connected to a crank chamber (28) of the internal combustion engine main body, and an outlet end (60B) supported by the cover member at a position located between the front wall and the carburetor.

An intake system for an internal combustion engine has at least one inlet channel through which air can flow and by which the air flowing through the inlet channel is to be conducted into at least one combustion chamber of the internal combustion engine. The inlet channel is, on the bottom side thereof, of flat form at least in one length region, wherein the flat bottom side extends as far as a tumble edge by which a tumbling flow of the air flowing into the combustion chamber can be effected.

A coupling system for attaching a first part to a second part using a locator and expansion shear pin is disclosed. The first part has a first flange and may be a formed part, such as an intake manifold. The second part has a second flange and may be a component, such as a throttle body, for attachment to the first part. The component includes a fastener-passing bore having an inner diameter. The locator and expansion shear pin extends perpendicularly from the first flange. The pin includes an expansion wall extending beyond the surface of the flange. A fastener-receiving bore is formed concentrically in the pin relative to the wall. The wall is expandable from a first diameter to a second diameter. The first diameter is less than the inner diameter of the fastener-passing bore. The second diameter is at least equal to the inner diameter of the fastener-passing bore.

Provided is a device used in the air induction tube of an internal combustion engine after the air filter and before the throttle body, and in particular to a device used to separate an air flow into a plurality of segments. The device can be made of two pieces. Each piece is initially a flat plate. A slit is formed half way through each plate and the corners are cut off or clipped. Each plate is then formed to have two generally curved portions. The pieces are joined via the slits resulting in the device. The pieces are generally perpendicular to each other at their intersection. The device is fitted into the air induction tube upstream of the throttle body, whereby it separates the air flow into distinct segments. The curved walls can be slightly compressed when inserted into an induction tube to hold the assembly in place.

An intake system for an internal combustion engine has at least one inlet channel through which air can flow and by which the air flowing through the inlet channel is to be conducted into at least one combustion chamber of the internal combustion engine. The inlet channel is, on the bottom side thereof, of flat form at least in one length region, wherein the flat bottom side extends as far as a tumble edge by which a tumbling flow of the air flowing into the combustion chamber can be effected.

In an internal combustion engine, an angle defined by an axis of a boundary of an intake port adjoining a valve seat and a cylinder axis is greater than an angle defined by the axis of the valve seat and the cylinder axis. A step between a first inner wall and a second inner wall, the first inner wall being a portion of an inner wall of the valve seat that is closest to the cylinder axis and the second inner wall being a portion of an inner wall of the boundary of the intake port that is closest to the cylinder axis. The first inner wall is located on the outer side in the radial direction of the intake port than the second inner wall.

A coupling system for attaching a first part to a second part using a locator and expansion shear pin is disclosed. The first part has a first flange and may be a formed part, such as an intake manifold. The second part has a second flange and may be a component, such as a throttle body, for attachment to the first part. The component includes a fastener-passing bore having an inner diameter. The locator and expansion shear pin extends perpendicularly from the first flange. The pin includes an expansion wall extending beyond the surface of the flange. A fastener-receiving bore is formed concentrically in the pin relative to the wall. The wall is expandable from a first diameter to a second diameter. The first diameter is less than the inner diameter of the fastener-passing bore. The second diameter is at least equal to the inner diameter of the fastener-passing bore.