Fastest Cars - Porsche 911 Turbo

PORSCHE 911 TURBO (1993) PORSCHE 911 TURBO (1995)
ENGINE Turbocharged flat-6 3600 cc Turbocharged flat-S 3600 cc
HORSEPOWER 360 bhp @ 5500 rpm 408 bhp@ 5750 rpm
TRANSMISSION Manual 5-speed Manual 6-speed 4WD
CHASSIS Unitary steel Unitary steel
BRAKES Discs all round with ABS Discs all round with ABS
TOP SPEED 174 mph (280 km/h) 181 mph (291 km/h)
ACCELERATION 0-60 mph 4.6 seconds 3,7 seconds 0-100 mph 10.6 seconds 9.2 seconds

Any Porsche 911 is a fast car but the Turbo range have been spectacularly fast since the launch of the first one in 1975. While BMW were the first manufacturer to attach a turbocharger to the exhaust system of a production car with the 19732002, Porsche arguably gave credence to the cult-following that was to keep growing long after BMW had dropped the idea. Twenty years on the cult is as strong as ever.

Motor racing has always had considerable influence .ovcr Porsche's management thinking. The company had enjoyed considerable success with the 917 during the 1969-72 Sports Car Championship until the ruling body killed the formula in favour of thinly disguised 2-seater Grand Prix cars. Porsche competition interest then switched to the Stateside Can-Am races where rules were less restrictive; initially open versions of the 917 were used with the 4.5 or 5-litre flat-12 engines of the earlier cars.

Seeking even more power, the engineers decided to turbocharge the existing engines rather than develop anything physically bigger; the ultimate version was the 917- 30 with the engine increased to 5.4-litres and turbocharged to produce a phenomenal 1100 bhp - it won the championship in 1973.

Meanwhile the sports car racing rules were set to change again for 1975 to cater for cars that at least looked like road cars (Group 5) and others that were road cars (Group 4). Armed with their recent turbo experience, Porsche began to develop a turbo-charged 911 and were running it during 1974 alongside the open two-seater cars.

This was to be the basis of the 935, which carried all before it when the championship finally started in 1976. However, a new car was also needed for the Group 4 category, a customary Porsche preserve; hence a road-going version of the 934 was launched in March 1975 - the Porsche Turbo. While the racing versions were able to develop over 500 bhp, and last the distance in endurance racing, the production car had a relatively leisurely 260 bhp from its 3-litre engine - enough for a comfortable 155 mph.

It still looked like a 911 from the side, but wide tyres with massive wheel arch flares and a big rear wing set the Turbo apart; the wing certainly helped to improve the stability at high speed as it always felt a little nervous when being driven fast. But despite all that power it was very tractable, with so much torque that Porsche only gave it four speeds.

When the 911 SC engine was increased to 3.2-litres in 1977, the Turbo went one better to 3.3-litres and 300 bhp in European trim, quite a big increase, helped by an intercooler to drop the temperature of the incoming air, and enough to take the maximum speed to 162 mph. While some 1983 revisions gave the engine more torque, the next major change was to wait until 1990, following a temporary cessation of Turbo production while the Carreras 2 and 4 came along.

The new version still used a 3.3-litre engine but, with further modifications, the power was raised to 320 bhp; installed in the cleaner Carrera 2 shape, this raised the maximum speed to 167 mph, and a five-speed gearbox helped to lower the 0-60 mph time to a dramatic 4.7 seconds. Late 1992 saw the arrival of the 3.6-litre version, outwardly unchanged apart from taller wheels, but now with 360 bhp and a 174 mph maximum speed. Vital tenths are difficult to shave from 0-60 mph times whatever the power increase, but particularly with a rear engine adding to the grip; this one recorded 4.6 seconds, but nearly a second off the 0-100 mph time showed that the new-found power was for real. But at Porsche development never stops.

When everyone thought the 911 had reached its peak they launched the Carrera Turbo, a Carrera 4 with twin turbos and 408 bhp, but everyone else just calls it Turbo. In reality it is a refined 959 with even more modern technology and with 4WD and a 6-speed box, it is almost as fast off the mark as the 959. Thirty years on and the same basic design now handles over three times the power with as much appeal to today's enthusiasts as the original 911 afforded back in 1965.