Abstract: The brake system includes a pedal, a pedal simulator, and a brake pedal unit. The brake pedal unit includes an input piston connected to the brake pedal for operating the pedal simulator during a normal braking mode. The brake pedal unit further includes first and second output pistons actuated by the input piston during a manual push through mode such that the first output piston generates brake actuating pressure at a first output of the brake pedal unit, and the second output piston generates actuating pressure at a second output of the brake pedal unit. The brake system further includes a hydraulic pressure source for supplying fluid at a controlled boost pressure, and a hydraulic control unit adapted to be hydraulically connected to the brake pedal unit and the hydraulic pressure source.