A high temperature alloy is disclosed. The high temperature alloy may have on a weight basis: about 9.0-10.0 weight % of Co, about 0.25 weight % maximum of Fe, about 8.0-9.0 weight % of Cr, about 4.75-5.50 weight % of Al, about 1.0-1.5 weight % of Ti, about 0-2.0 weight % of Mo, about 6.0-9.0 weight %, of W, about 0.12-0.18 weight % of C, about 0.01-0.03 weight % of Zr, about 0.005-0.015 weight % of B, about 0.5-1.5 weight % of Ta, a balance of Ni, and incidental impurities.

A high temperature alloy is disclosed. The high temperature alloy may have on a weight basis: about 9.0-10.0 weight % of Co, about 0.25 weight % maximum of Fe, about 8.0-9.0 weight % of Cr, about 4.75-5.50 weight % of Al, about 1.0-1.5 weight % of Ti, about 0-2.0 weight % of Mo, about 6.0-9.0 weight %, of W, about 0.12-0.18 weight % of C, about 0.01-0.03 weight % of Zr, about 0.005-0.015 weight % of B, about 0.5-1.5 weight % of Ta, a balance of Ni, and incidental impurities.

A method for manufacturing a poppet valve or mushroom valve includes providing a mixture of metal powder and a binder, filling and pressing said mixture in a mold, to obtain a green product, removing the binder from the green product, and thermally sintering the green product to a poppet valve blank, by hot isostatic pressing. A poppet valve is also provided that is manufactured with this method.

A combustion engine comprises combustion chambers (1-4) with reciprocating pistons (5), intake ports (6) and exhaust ports (7). Overflow ports (11,12) are provided between adjacent combustion chambers to provide an overflow channel (15,16) that closes during a high load mode of operation of said engine and opens during a partial load mode of operation. The overflow ports (11,12) straddle a path of shortest distance between adjacent combustion chambers and said overflow channel (15) extends at least substantially along said path of shortest distance. In a further aspect of the invention, exhaust ports (1b+2a, 3b+4a) of adjacent combustion chambers are joined into a common exhaust channel (P2,P4) that communicates with an exhaust header (20) of the engine through valve means (V1,V2) that open during the high load mode of operation of said engine and close during a partial load mode of operation.

A combustion engine comprises combustion chambers (1-4) with reciprocating pistons (5), intake ports (6) and exhaust ports (7). Overflow ports (11,12) are provided between adjacent combustion chambers to provide an overflow channel (15,16) that closes during a high load mode of operation of said engine and opens during a partial load mode of operation. The overflow ports (11,12) straddle a path of shortest distance between adjacent combustion chambers and said overflow channel (15) extends at least substantially along said path of shortest distance. In a further aspect of the invention, exhaust ports (1b+2a, 3b+4a) of adjacent combustion chambers are joined into a common exhaust channel (P2,P4) that communicates with an exhaust header (20) of the engine through valve means (V1,V2) that open during the high load mode of operation of said engine and close during a partial load mode of operation.

A rocker arm, comprises a first outer arm and a second outer. A pivot body is joined between the first end of the first outer arm and the third end of the second outer arm. An actuatable latch mechanism is within the pivot body. An inner arm assembly comprises a latch arm pivotable adjacent the pivot body. An axle joins the inner arm assembly to pivot between the first outer arm and the second outer arm. An outer arm connector spans between the second end of the first outer arm and the fourth end of the second outer arm. A valve seat insert is constrained within the inner arm assembly between the outer arm connector and the axle. Alternatively, a valve seat insert hangs from the axle and is constrained within the inner arm assembly, the valve seat insert comprising a front and a rear cusp.

A valve arrangement for supplying air to an internal combustion engine includes a first valve and a second valve arranged within the first valve. A valve guide for use in a valve arrangement is also provided.

A high temperature alloy is disclosed. The high temperature alloy may have on a weight basis: about 9.0-10.0 weight % of Co, about 0.25 weight % maximum of Fe, about 8.0-9.0 weight % of Cr, about 4.75-5.50 weight % of Al, about 1.0-1.5 weight % of Ti, about 0-2.0 weight % of Mo, about 6.0-9.0 weight %, of W, about 0.12-0.18 weight % of C, about 0.01-0.03 weight % of Zr, about 0.005-0.015 weight % of B, about 0.5-1.5 weight % of Ta, a balance of Ni, and incidental impurities.

An intake valve for a combustion engine is described. The intake valve has a head portion that is designed to improve the flow of air-fuel mixture around the head portion and into the combustion chamber. The head portion has a beveled or rounded edge at the top surface. The angle changes from the underside surface to the top surface are rounded to prevent separation of the air-fuel mixture from the surface of the intake valve. In addition, the underside surface of the head portion has a plurality of helical grooves that induce a circular flow to improve mixing of the air-fuel mixture in the chamber. The helical grooves also improve heat exchange between the air-fuel mixture and the intake valve.

An intake valve for a combustion engine is described. The intake valve has a head portion that is designed to improve the flow of air-fuel mixture around the head portion and into the combustion chamber. The head portion has a beveled or rounded edge at the top surface. The angle changes from the underside surface to the top surface are rounded to prevent separation of the air-fuel mixture from the surface of the intake valve. In addition, the underside surface of the head portion has a plurality of helical grooves that induce a circular flow to improve mixing of the air-fuel mixture in the chamber. The helical grooves also improve heat exchange between the air-fuel mixture and the intake valve.