An F6 engine, also known as a flat-six or horizontally opposed six, has six cylinders arranged in two banks of three cylinders on each side of a central crankshaft. This design offers a low center of gravity and can provide smooth power delivery. It differs from other flat-six designs primarily in its specific internal components, tuning, displacement, and application. For example, Porsches flat-six engines used in their 911 models have evolved over years with different displacements and technologies like turbocharging but maintain the characteristic layout.