Why a Porsche Air-Cooled Engine has a Unique Sound
The sound of an air-cooled Porsche flat-six engine is unique in the automotive world and is one of the defining characteristics of early Porsches. The sound is particularly resonating as an air-cooled Porsche is carving a mountain curve with the power being applied.

But why does a air-cooled Porsche sound different? It all comes down to the Porsche flat-six engine design that has defined the brand from the beginning.
Water in an engine block not only provides cooling for the engine but it also provides sound insulation. Without the water-ways in the case one hears the true mechanics of the engine in operation.
In addition to the lack of water providing sound insulation, early air-cooled engines expressed valvetrain clatter and whirring noises of the fan required to cool the engine.
The sound and design of an air-cooled flat-six Porsche engine came to define Porsche. Not only was the sound unique and different, but the flat-six engine design led to Porsche success on the race track leading to its success in the showroom.