A fuel injection supply system includes an intensifier cylinder having an
intensifier piston configured to pressurize fuel in an intensifier
chamber of the cylinder during a pressurizing stroke, and further
configured to draw fuel into the intensifier chamber during a recharge
stroke. A fuel rail receives pressurized fuel from the intensifier
chamber, and supplies the fuel to a plurality of fuel injectors. A
control unit controls switching of the intensifier piston between a
pressurizing stroke and a recharge stroke, controlling recharge strokes
of the piston to occur between two consecutive injection events of the
plurality of fuel injectors. The common fuel rail may be hydraulically
locked except during injection events of any of the plurality of fuel
injectors, or during a recharge stroke of the piston. The intensifier
piston may be controlled to perform a recharge stroke once during each
engine cycle, or more than once during each engine cycle.