A pump barrel (70) for use in a hydrostatic pump assembly includes a barrel body (88) defining a plurality of piston bores (84) that receive a plurality of pistons moveable within the bores, and a porting face (74) that defines a plurality of ports (72) in fluid communication with the piston bores and providing fluid flow paths into and out from the barrel body. Each port (72) has a leading edge surface and a trailing edge surface relative to a direction of rotation of the pump barrel, said leading and trailing edge surfaces being oriented in a first direction (along line 6-6) at non-right angles relative to the porting face (74). Each port (72) has an inner edge surface (80) and an outer edge surface (82) relative to a radial direction of the pump barrel, said inner and outer edge surfaces (80,82) being oriented in a second direction (along line 9-9) comprising a tilt angle (90,92) relative to the porting face (74) that is different from the angles in the first direction. A hydrostatic pump assembly incorporating such a pump barrel (70) is also disclosed.