BMW M3 and M4 return to inline-six cylinder engines image

During the German company’s M3 and M4 technology days, official sources confirmed several technical aspects about the upcoming sport models.

According to the preliminary technical specifications released, power will come from a brand new high-revving inline-six 3.0-liter TwinPower Turbo engine outputting around 430 hp (316 kW) at 7,500 rpm and a maximum torque of more than 500 Nm (369 lb-ft).

Besides being more powerful than the outgoing naturally aspirated V8, the new power mill is also less thirsty, enabling the M3 Sedan to have 25% lower fuel consumption and CO2 emissions. BMW also mentions they were able to lower the M3 Sedan’s weight to less than 1,500 kg (3,306 lbs).

“Four generations of the BMW M3 have blended motor sport genes and uncompromised everyday usability within an emotionally rich overall concept;” explains Dr Friedrich Nitschke, President BMW M GmbH.

“The BMW M3 Sedan and BMW M4 Coupe represent an ongoing commitment to this philosophy. The engine is the heart of every M model, and the example fitted in the two new cars combines the virtues of a high-revving naturally aspirated unit with the strengths of turbocharger technology. An all-embracing lightweight design concept keeps the cars’ weight to just less than 1,500 kilograms. The BMW M3 and BMW M4 take motor sport technology from the track to the road, and thousands of laps of the legendary Nürburgring Nordschleife – the world’s most demanding racetrack – have readied the new models for that transition. Meticulous and passion-fuelled development work has underpinned the creation of two high-performance sports cars that set new standards in terms of overall concept, precision and agility.”

We also found out that the new engine, dubbed S55, has a closed-deck crankcase design and comes with two mono-scroll turbochargers. BMW’s engineers implemented a forged crankshaft, which is not only lighter but also more rigid, and thanks to the diminished rotating masses it enables the engine to provide better acceleration and response.

Nitschke also hinted there could be a resurrection of the CSL moniker, with a planned lighter version, tipping the scales at around 1,400 kg (3,086 lbs) thanks to a more simplistic interior cabin, lightweight seats and other weight-saving techniques.