Abstract: The invention relates to combustion catalyst compositions which when blended into liquid hydrocarbon-base fuels reduce deposits in fuel combustion systems, inhibit corrosion in fuel systems and facilitate a more efficient oxidation of fuel. The combustion catalyst compositions comprise a surface-active/emulsifier agent, a lubricating oil and a liquid saturated hydrocarbon having the general formula C.sub.n H.sub.2n+2 wherein n is from 14 to 17.

Abstract: A compression ring is provided for mounting in an annular groove formed in a piston head utilized in an internal combustion engine. The ring includes an inner section positionable within the groove and an outer section protruding from the groove for sliding sealing engagement with the wall of the cylinder in which the piston head is reciprocally mounted. The ring inner section is provided with opposite side surfaces. Each side surface includes a first segment extending inwardly from the outer section and being in substantially parallel relation with an adjacent side wall of the groove in which it is accommodated. The ring side surface also includes a second segment which is angularly disposed relative to and extends inwardly from the first segment and is in continuous spaced relation with the adjacent side wall of the groove. The distance between the first segments of the ring inner section side surfaces are less than the distance between the side walls of the groove.