Abstract: A fluid pressure driven power system having a plurality of rotors keyed to a shaft rotatably journaled within a casing having, the rotors each having a plurality of fins extending around its periphery with the fins projecting above the perimeter of the rotor. A pressure head mounted within the casing with the casing having a plurality of tubular inserts embedded therein. Each of the tubular inserts having an exposed longitudinal end portion in tangential alignment with the fins on a rotor. Each insert end portion having a cutaway section that is upwardly arcuately compressed to overlie the fins on rotors rotating beneath the pressure head. Each compressed cutaway portion is formed with an orifice opening from the tubular insert. A pressurized fluid source can be selectively connected to one or more of the tubular inserts to provide pressurized fluid for discharge through the orifices.