A liquid propellant rocket engine includes a main turbo-pump and a boost turbo-pump. The main turbo-pump has a main pump with an outlet that is fluidly coupled with a supply line. The boost turbo-pump includes a housing, a rotor, a boost pump, and a turbine. The boost pump includes a first portion of the housing and a first portion the rotor. The turbine includes a second portion of the housing and a second portion of the rotor. The turbine has turbine blades attached to the second portion of the rotor and an inlet fluidly coupled with the supply line. The turbine has a plurality of circumferentially disposed feed lines defined by the second portion of the housing and not the first portion of the housing. The feed lines are fluidly coupled between the inlet and the turbine blades. The feed lines have an acute angle turn.