2011 4:42 PM The 198bhp Vauxhall Insignia BiTurbo. Bringing big grunt to a motorway near you Thumping diesel fans take note. This is the new Vauxhall  Insignia BiTurbo and it packs the most powerful diesel engine ever seen in the curvy mid-sizer; all 198bhp and 400Nm (torque) of it. Prices start