The disclosure includes manufacturing a semimanufactured cylinder head (3) having a shielding curtain portion (16g) and spraying metal powder (P) onto an annular valve seat portion (16f) using a cold spray method to form a valve seat film (16b). The shielding curtain portion (16g) projects in an annular shape from an annular edge portion of an opening portion (16a) of an intake port (16) or an opening portion (17a) of an exhaust port (17) toward the center (C) of the port. The annular valve seat portion (16f) is located on an outer side of the port than the shielding curtain portion (16g).

A valve seat insert includes a top convex arcuate blend for improving fluid flow, and a valve seating surface for slowing down valve recession. The valve seating surface includes a radially outer convex arcuate segment defining an outer radius of curvature forming a first wear crown for contacting the valve at an early wear state, a radially inner convex arcuate segment defining an inner radius of curvature forming a second wear crown for contacting the valve at a later wear state, and a linear segment extending between the radially outer convex arcuate segment and the radially inner convex arcuate segment.

A valve seat insert includes a top convex arcuate blend for improving fluid flow, and a valve seating surface for slowing down valve recession. The valve seating surface includes a radially outer convex arcuate segment defining an outer radius of curvature forming a first wear crown for contacting the valve at an early wear state, a radially inner convex arcuate segment defining an inner radius of curvature forming a second wear crown for contacting the valve at a later wear state, and a linear segment extending between the radially outer convex arcuate segment and the radially inner convex arcuate segment.

A fuel injector includes an injector housing defining a longitudinal axis, and including a body piece having formed therein a fuel inlet defining a transverse axis intersecting the longitudinal axis. The injector housing further includes a nozzle having formed therein a plurality of spray outlets, and including a nozzle terminal tip. The injector housing further includes a locating surface axially inward of the nozzle terminal tip and extending circumferentially around the nozzle. A first axial distance (AD) is defined between an intersection of the transverse axis and the longitudinal axis, and the nozzle terminal tip. An exposed tip length axial distance (TL) is defined between the locating surface and the nozzle terminal tip. A ratio of AD to TL is from 8.06 to 8.34.

A vehicle that can cool an ignition coil is provided. The vehicle has an engine having a cylinder head and an ignition coil with a first end exposed from the cylinder head, a CVT that varies and outputs rotary power from the engine, and an exhaust duct having a first exhaust port for exhausting a gas within a CVT case to outside of the CVT case, and a second exhaust port for exhausting a part of the gas flowing to the first exhaust port to outside of the CVT case, wherein the second exhaust port is provided for exhausting the gas within the CVT case to at least a part of the first end of the ignition coil.

A vehicle that can cool an ignition coil is provided. The vehicle has an engine having a cylinder head and an ignition coil with a first end exposed from the cylinder head, a CVT that varies and outputs rotary power from the engine, and an exhaust duct having a first exhaust port for exhausting a gas within a CVT case to outside of the CVT case, and a second exhaust port for exhausting a part of the gas flowing to the first exhaust port to outside of the CVT case, wherein the second exhaust port is provided for exhausting the gas within the CVT case to at least a part of the first end of the ignition coil.

Cylinder cover for an internal combustion engine, comprising a cylinder head, a cylinder head cover, an intermediate flange arranged between the cylinder head and the cylinder head cover, a plurality of fasteners for fastening the cylinder head cover and the intermediate flange to the cylinder head. The plurality of fasteners comprising a first fastener having a first head with internal threads, and a first shaft with first external threads, and a second fastener comprising a second head, and a second shaft with second external threads. The first fastener fastens the intermediate flange to the cylinder head and the second fastener fastens the cylinder head cover to the intermediate flange.

Cylinder cover for an internal combustion engine, comprising a cylinder head, a cylinder head cover, an intermediate flange arranged between the cylinder head and the cylinder head cover, a plurality of fasteners for fastening the cylinder head cover and the intermediate flange to the cylinder head. The plurality of fasteners comprising a first fastener having a first head with internal threads, and a first shaft with first external threads, and a second fastener comprising a second head, and a second shaft with second external threads. The first fastener fastens the intermediate flange to the cylinder head and the second fastener fastens the cylinder head cover to the intermediate flange.

A combustion chamber structure in which an installation hole of the injector is improved to realize a rapid combustion and to reduce an unburned hydrocarbon. In the combustion chamber, a leading end of an injector is withdrawn from an upper end of an opening of an installation hole, and an additionally expanded surface area is formed on an upper inner surface of the installation hole from a portion to which the leading end of the injector is situated. to an opening end of the installation hole. An angle between the additionally expanded surface area and a joint surface of a cylinder head is narrower than an angle between a center axis of the installation hole and the joint surface.

Methods and systems are provided for a fuel injector of an internal combustion engine. In one example, a fuel injector includes a body having a flange shaped to seat within a shoulder of a passage of a cylinder head. The shoulder is positioned at an inner side of the cylinder head such that the fuel injector is coupled to the cylinder head at the inner side by the flange.