It delivers 228bhp between 5200rpm and 6000rpm, along with 236lb ft from just 1250pm through to 4800rpm.
These are a 20bhp and 29lb ft increases on the turbocharged 1.6-litre four-cylinder petrol engine used by the second-generation Cooper S John Cooper Works, and is 39bhp and 25lb ft more than that offered by the milder version of the turbocharged 2.0-litre four-cylinder petrol engine used in the third-generation Cooper S.
Although it does without a mechanical limited-slip differential, the new JCW receives an electronic differential lock to help transmit its reserves to the road.
Buyers can choose between either a standard six-speed manual gearbox or an optional six-speed automatic transmission with steering wheel-mounted shift paddles.
At 1205kg, the three-door hatchback tips the scales 100kg less than the model it replaces. It is claimed to hit 62mph in just 6.3sec and reach a top speed of 153mph in manual guise – 0.6sec and 7mph faster respectively than the old JCW, and a similar 0.6sec and 9mph improvement on the new Cooper S.
The automatic gearbox adds 15kg to the kerb weight, taking it up to 1220kg. However, shorter first and second gear ratios see it provide added off-the-line performance, giving a 0-62mph time of just 6.1sec and the same 153mph top speed as the manual.
Combined cycle fuel consumption is claimed to be 42.2mpg, along with average CO2 emissions of 155g/km with the manual gearbox. These figures improve to 49.7mpg and 133g/km resepctively when the car is optioned with an automatic gearbox.
Mini’s latest performance hero rides on standard 17-inch wheels shod with 205/45 profile tyres, although 18-inch rims are available as an option. Along with specific suspension tuning, the new car also receives a Brembo brake system.
Inside, the new JCW sports a number of unique touches, including model-specific sill decoration, more supportive front seats with integrated headrests, a three-spoke multi-function steering wheel, a new gear lever, stainless steel pedals and revised instrument graphics.
Despite the recent introduction of a new five-door variant of the Cooper S, Mini says there are no immediate plans to use it as the basis of an additional John Cooper Works model.
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