The BMW M135i and M235i were never lacking in pace or dynamism, but BMW has now usurped the old car with the M140i and M240i which deliver more power and therefore more performance. Rather than the not insignificant 321hp and 332 ft lb of torque that the previous ‘35i’ gen car had, BMW has breathed an extra 14hp and 37 ft lb of torque into the turbocharged Baukasten six-cylinder 3.0-litre engine.
While the extra oomph doesn’t look like a lot on paper, the additional power has improved the car’s performance figures with each car taking just 4.6 seconds to hit 60 when equipped with the six-speed auto box (4.8 with the manual). The convertible M240i also puts in good times despite its 160kg weight penalty, covering the sprint in 4.7 seconds with the auto box and 4.9 with the manual. Top speed is the usual electronically limited 155mph.
On the road both the M140i and M240i are absolute peaches. There is plenty of power across the rev range and turbo lag is negligible in almost all situations. BMW has also avoided making these cars mid-range heroes; the engine loves to rev and does so very sweetly indeed. They handle too, though this is the only situation in which the M240i convertible demonstrates any weakness as it isn’t quite as sharp as its hard-top compatriots. The difference is negligible, however, and the convertible certainly scores points for letting you hear that creamy straight-six and the now well known ‘whump’ between gear changes.
It might not be the first thing on your mind if you’re after a performance car, but the revised engine offers improved economy and lower emissions. Up to 38.9mpg is possible in the auto and thanks to the fact it produces less CO2 the more powerful ‘40i’ cars are cheaper to tax than the previous ‘35i.
Prices start at a shade under £32,000 and for the performance on offer – and as a basis for making a very fast BMW – we don’t think you can do much better.