THE new 3.0-litre straight six is basically the 2.8-litre BMW six with the bore lengthened from 84mm to 89.6mm - a move which plays a part in lifting power from 142kW to 170kW at 5900rpm - and a refined Double VANOS variable valve timing system that increases intake valve lift and duration. The impressive maximum torque of 300Nm comes in at 3500rpm - and 90 per cent of this is available from 1500rpm. Reduced piston friction and a lower idle speed mean fuel consumption remains the same as the previous, smaller engine. In the manual-transmission convertible, this means a city figure of 10.7 litres/100km and a highway figure of 6.6 litres/100km.