911 TECH THE MEZGER SIX

Despite the protests of diehards, Porsche, as is now well understood, had no option but to abandon the air-cooled flat six. Noise and emissions regulations plus ever more demanding mpg requirements were making it impractical to adapt the 911’s traditional engine design further. Porsche was also the last significant builder of air-cooled engines and the possibility of sharing parts costs was therefore non-existent. The flat six was also expensive to build. The company’s attempts to develop it with a multi-valve head came to grief with the Typ 965, which was foiled by cooling problems, and a water-cooled, 24-valve head as on the 959 was a complex and far too expensive solution for the 911. The 21st century