Mini has completed its John Cooper Works line-up with petrol-powered versions of the Cooper and Convertible. Both cars will come fitted with a 2.0-litre four-cylinder turbocharged engine though vehicle performance figures will differ slightly between the two. The hatch produces a total of 231bhp and 380Nm of torque. It can do 0-100 km/h in around 6 seconds and will go on to a top speed of 250 km/h. The drop-top version comes with 228bhp but has the same torque levels and its top speed is 245 km/h with a 0-100 km/h speed slightly about 6 seconds. All cars come fitted with a dual-clutch automati…