Abstract: A diesel fuel additive composition, a fuel containing the fuel additive, a method for improving diesel engine performance using the additive and a method for making the additive for diesel engines having a high pressure fuel injection system. The fuel additive has a number average molecular weight (Mn) of from about 500 to about 10,000 and is selected from a hydrocarbyl-substituted succinic acid or anhydride or derivative thereof and a hydrocarbyl-substituted Mannich base. The additive has a molecular weight distribution such that less than about 25 wt. % of the additive has a molecular weight of 400 or less as measured by gel permeation chromatography (GPC) based on a polystyrene calibration curve.

Abstract: A diesel fuel additive composition, a fuel containing the fuel additive, a method for improving diesel engine performance using the additive and a method for making the additive for diesel engines having a high pressure fuel injection system. The fuel additive has a number average molecular weight (Mn) of from about 500 to about 10,000 and is selected from a hydrocarbyl-substituted succinic acid or anhydride or derivative thereof and a hydrocarbyl-substituted Mannich base. The additive has a molecular weight distribution such that less than about 25 wt. % of the additive has a molecular weight of 400 or less as measured by gel permeation chromatography (GPC) based on a polystyrene calibration curve.

Abstract: A fuel injection valve and director plate assembly including a circular beveled valve seat, a valve ball for forming a circular sealing line against the seat, and a perforated director plate. The improved valve seat is substantially thicker than a prior art seat to provide greater mass of seat material and hence reduced vulnerability of the seat to thermal distortion from welding. To obviate an increase in residual fuel volume that would result from displacing the director plate from the valve by the added thickness of the seat, the central portion of an improved director plate is made concave such that the actual fuel-directing portion of the director plate is to the valve ball in the prior art relationship, thus preserving the desirably small prior art volume of residual fuel after valve closing.

Abstract: An improved fuel injection spray director plate including conically chamfered entries to the flow passages through the plate. The conical chamfer may extend part way or all the way through the plate. In a currently preferred embodiment, the chamfer extends only part way through the plate, and the remaining cylindrical portion of the passage provides desirable directional capability for the spray. Preferably, the conical chamfer axis forms an angle with the cylindrical portion axis. Preferably, a flow passage is positioned in the director plate such that the main flow direction of fuel exiting the fuel injector valve is received into the chamfer of the passage. Preferably, a second conical portion is formed in the passage between the first conical portion and the cylindrical portion.

Abstract: A director plate for a fuel injector for use in an internal combustion engine. A plurality of fuel passages extend through the plate between an inlet surface and an exit surface. The passage and exit surfaces are extremely smooth, having an average surface roughness (Ra) less than about 0.2 ?m, and preferably less than about 0.1 ?m. The corners of the exits are sharp and are free of features such as break-edges, burrs, and remelt. The surface quality may be obtained via any means of surface finishing.