M3 Sedan and M4 Coupe to debut in Detroit

BMW has pre-released photos and details of its 2015 M3 Sedan and M4 Coupe models, which will make their public debuts at the North American International Auto Show in Detroit in January.

Apart from being based on the new 3 Series/4 Series architecture, the big news surrounding the new M models is their return to use of an inline-six-cylinder engine configuration, like their famous forebears.

The all-new, twin-turbocharged 3.0-litre engine is said to be some 10 kg lighter than its V-8 predecessor and even more powerful, with an output of 425 horsepower from 5,500 to 7,300 rpm and 406 lb-ft of torque from 1,850 to 5,500 rpm

BMW says it's capable of accelerating from 0-to-97 km/h (0-60mph) in 3.9 seconds when equipped with the M-DCT (double-clutch) transmission (4.1 seconds with standard 6-speed manual).

Thanks to dedicated lightweight construction, including the increased use of carbon-fibre-reinforced plastic (CFRP) and aluminum, the M3 is said to be about 80 kg lighter than its outgoing counterpart, with similar weight saving in the M4.

In order to accentuate the racing character of the two models in terms of both their technical composition and the fine-tuning of the cars, BMW says, their engineers worked closely with BMW Motorsport’s professional racing drivers, including Bruno Spengler and Timo Glock, during the development phase which involved extensive testing and set-up work carried out at the Nürburgring-Nordschleife circuit.

North-American sales of both models are scheduled to begin in early summer, 2014.