A system for optimizing performance of an engine, including an intake manifold with an upper mount, plenum floor defining a plenum opening, lower mount defining intake openings, and intake runners communicating between the plenum and intake openings. The upper mount may be coupled to an air inlet device and the lower mount may be coupled to a cylinder head. A mountable device has an upper portion and lower portion and is configured to be inserted through the upper mount of the intake manifold to be coupled to the plenum floor so the mountable device covers the plenum opening and at least the upper portion of the mountable device remains between the upper mount and the plenum floor. A fixation system is configured align the mountable device to the intake manifold and to prevent the mountable device from decoupling from the plenum floor during engine operation. The mountable device is interchangeable without removing the intake manifold from the cylinder head.

An engine component includes a tubular member, of stratified layers, curved on both ends and comprising outwardly protruded nozzles located on one side. Each of the nozzles comprising an elongated body and a tip defining apertures. The tubular member forms a nitrous oxide delivery apparatus configured to increase an internal combustion engine's power output and is located in a cavity of an intake manifold such that there is no seal between the member and the manifold.

An engine component includes a tubular member, of stratified layers, curved on both ends and comprising outwardly protruded nozzles located on one side. Each of the nozzles comprising an elongated body and a tip defining apertures. The tubular member forms a nitrous oxide delivery apparatus configured to increase an internal combustion engine's power output and is located in a cavity of an intake manifold such that there is no seal between the member and the manifold.

A suction tube of a stratified scavenging engine that can improve the flexibility in designing the shapes and layouts of an air-fuel mixture passage and an air passage; allow for continuous and smooth changes in the shapes of the cross sections of the air-fuel mixture passage and the air passage from the inlet side toward the outlet side; reduce the number of components; and facilitate attachment and assembly; and that is also advantageous in terms of cost is provided. The suction tube includes an air-fuel mixture passage and an air passage, inlet and outlet sides of the passages being connected to a carburetor and a cylinder, respectively; a cylindrical exterior member that mainly forms an outer perimeter portion of each of the air-fuel mixture passage and the air passage; and an interior member for dividing the inside of the cylindrical exterior member into the air-fuel mixture passage and the air passage. With the use of elastic deformation of the interior member or the cylindrical exterior member, the interior member is attached to and integrally formed with the inside of the cylindrical exterior member.

A system for optimizing performance of an engine, including an intake manifold with an upper mount, plenum floor defining a plenum opening, lower mount defining intake openings, and intake runners communicating between the plenum and intake openings. The upper mount may be coupled to an air inlet device and the lower mount may be coupled to a cylinder head. A mountable device has an upper portion and lower portion and is configured to be inserted through the upper mount of the intake manifold to be coupled to the plenum floor so the mountable device covers the plenum opening and at least the upper portion of the mountable device remains between the upper mount and the plenum floor. A fixation system is configured align the mountable device to the intake manifold and to prevent the mountable device from decoupling from the plenum floor during engine operation. The mountable device is interchangeable without removing the intake manifold from the cylinder head.

A suction tube of a stratified scavenging engine that can improve the flexibility in designing the shapes and layouts of an air-fuel mixture passage and an air passage; allow for continuous and smooth changes in the shapes of the cross sections of the air-fuel mixture passage and the air passage from the inlet side toward the outlet side; reduce the number of components; and facilitate attachment and assembly; and that is also advantageous in terms of cost is provided. The suction tube includes an air-fuel mixture passage and an air passage, inlet and outlet sides of the passages being connected to a carburetor and a cylinder, respectively; a cylindrical exterior member that mainly forms an outer perimeter portion of each of the air-fuel mixture passage and the air passage; and an interior member for dividing the inside of the cylindrical exterior member into the air-fuel mixture passage and the air passage. With the use of elastic deformation of the interior member or the cylindrical exterior member, the interior member is attached to and integrally formed with the inside of the cylindrical exterior member.