The car with three names: Vauxhall in the UK, Opel in the rest of Europe, and Buick Regal in North America, has been given a new, more powerful 4-cylinder diesel engine. Based on the existing 2.0CDTi used on models such as the Insignia, Astra and Zafira Tourer, the Insignia BiTurbo has been given twin-sequential turbochargers boosting power by 35 to 195hp and peak torque by 37 to 295lb-ft. Performance numbers have invariably improved with a 0-62mph time of 8.7 seconds and a top speed of 143mph.

Yet the BiTurbo is more fuel efficient due to a host of eco features including a Start/Stop system. "In this class of power and torque, six-cylinder diesel engines with around three liter displacements are the usual choice. With our BiTurbo technology smaller engines produce even more output while enabling 30 percent lower fuel consumption and emissions," says Insignia chief engineer, Volker Scharf. Available with a choice of Sports Tourer and five-door Hatch in SRi, Sri Vx-line and Elite trims, prices in the UK for the Insignia BiTurbo start from £27,120 OTR.