THE POWER OF THREE

The impact-bumper 911 ran from 1974 to 1989 and superficially evolved relatively little: bodies were galvanised from 1976, suspensions were steadily upgraded, engines increased in capacity from 2.7 to 3.0 litres and finally to the 3,164cc of the 3.2 Carrera. The ‘middle generation’ 1978 SC was visually almost identical to the 2.7 and Carrera 3.0-litre models it replaced. The important changes were under the skin, especially the flat six, which was extensively refined.

Although the SC inherited the Carrera 3.0-litre’s 95x70.4mm bore and stroke and its 8.5:1 compression ratio, there was much internal reworking to improve efficiency, if not (initially) outright power. The SC used the thicker crankshaft and main bearings of the 3.3 Turbo, but thinner connecting rods. The Turbo’s breakerless ignition was used instead of traditional points and electronic rather than mechanical cut-out for the rev limiter brought both greater precision and economy. The emphasis was to improve drivability through better