Flat boxer engines are internal combustion engines consisting of four cylinders and four pistons for automobiles or two cylinders and two pistons for motorcycles. A pair of cylinders are horizontally placed 180 degree from each other and the pistons present inside the cylinder move in opposite direction to each other. Flat boxer engine was first invented by Karl Benz in 1896. They are known as boxer engines as the movement of engine pistons are similar to the act of boxers throwing punches on each other. Flat boxer engines are used in passenger vehicles that allow power generated by the engine to flow directly into transmission. Flat boxer engines provide better fuel efficiency to all-wheel drive (AWD) vehicles compared to their counterpart, front wheel drive (FWD) vehicles. Flat boxer engines have a low center of gravity, thus lowering the center of gravity of vehicles. Low center of gravity help vehicles with flat boxer engines to more easily maneuvers. In flat boxer engines, pist...