911 - Since 1965, Porsche's rear engined six cylinder models have been called the 911. Porsche originally designated the model as the 901, but Peugeot objected as they felt that they owned all model designations with a '0' in the middle. (Something that they seemed to forget when Ferrari launched the 308!) Indeed, for many people a 911 is a Porsche, and vice versa. From 1965 to 1989, it was all pretty sensible. The car was the 911. That's all there was to it. There were constant changes, above and below the skin. Above the skin, the impact bumper cars arrived in 1974. Under the skin, engine and brakes were upgraded constantly. Launched with an engine capacity of 2 litres, by 1974, the engine had grown to 2.7 litres.
In impact bumper guise, the 911's engine grew to 3 litres for the 3.0 Carrera and the SC models from 1978 to 1983. For 1984, the 911 became the Carrera (but was, of course, still a 911) and the engine grew to 3.2 litres. In 1987, the 911 received a hydraulic clutch to replace the cable operated clutch which it had used from 1965 and the 915 gearbox made way for the G50 gearbox.
964 - The first re-working of the 911 was the Type 964, launched in 1989 as the Carrera 2 and Carrera 4. The 964 marked the start of the 911's gradual migration from a purist's sports car to a luxury sports car. ABS and power steering made the driver's life more comfortable. Engine capacity was up to 3.6 litres in the normally aspirated versions, and each cylinder boasted two spark plugs.
993 - The 993, which arrived in 1994, is widely regarded as the high point of the 911's development and was the end result of 30 years of development of aircooled 911 models.
996 - After 35 years the air cooled engine finally gave way to a water cooled engine in 1998. Like all 911's, the 996 was well received by the motoring press. The styling was somewhat challenging, in part due to the "fried egg" headlights, and in part due to the fact that those headlights were shared with the entry level Boxster range. Recently that very difference seems to be counting in the 996's favour as a clear point of difference.
997 - The simplest way to tell the 997 model from the 996 that preceded it is the return to a round headlight which arrived in 2005.
