Low mass roller valve lifter assembly

A roller valve lifter assembly comprising a roller valve lifter and a sleeve reciprocably receiving the valve lifter,

• the valve lifter including
• a cylindrical body having first and second ends, said first end being slotted to form a pair of spaced legs having a pair of openings in said legs aligned on a transverse axis,
• a roller having a central bore received between said legs with the bore aligned on the axis, and
• a shaft received in the openings and extending through the bore to rotatably journal and support the roller between the legs, the shaft having opposite ends extending beyond the cylindrical body, and
• the sleeve having a transverse slot open at one longitudinal end and receiving the shaft ends for reciprocation therein, the shaft ends being engageable with edges of the slot to prevent rotation of the lifter in the sleeve,
• wherein the cylindrical body has an outer diameter smaller than a maximum dimension of the roller parallel with a body diameter but the sleeve has an outer diameter larger than said maximum dimension of the roller, the sleeve being slotted in a direction normal to the shaft axis to receive protruding portions of the roller.