http://www.bath.ac.uk/~ccsshb/12cyl/ Some facts on the 14 cylinder version: Total engine weight: 2300 tons (The crankshaft alone weighs 300 tons.) Length: 89 feet Height: 44 feet Maximum power: 108,920 hp at 102 rpm Maximum torque: 5,608,312 lb/ft at 102rpm
Simplicity, no valvetrain to build and maintain. Also, more power strokes, alot less wasted motion and energy.