The MINI Cooper SD is powered by a brand new 105 kW/143 hp 2.0L four-cylinder turbodiesel unit with more torque than any other engine in the range – 305 Nm (225 lb-ft). The idea is to offer the fun of a Cooper S with excellent fuel economy similar to the Cooper D’s. Fifth Gear takes the car by the scruff of its neck to find out if it really is the perfect balance…