Benz inline six driven by efficiency

The return of six-cylinder inline engines to the Mercedes-Benz line-up will be driven by development, production and packaging efficiencies. That's the message from the German luxury brand giant's head of research and development, Thomas Weber.

Although Weber stopped short of confirming the new engine family's existence and its expected debut in next year's new generation E-Class, the senior Daimler executive did reinforce the logic of returning to the engine layout.

Describing Mercedes-Benz as a brand built on inline sixes, Weber detailed how a return to an inline six-cylinder would leverage technology born of the new-generation four-cylinder engines Mercedes is using in its A and C-Class families.

"We are a company coming from inline sixes. It has been a success factor in the past. [But] We now must dislink [sic].

"It would be completely fine looking forward [to continue with V6s] but regarding a combination of four and six cylinder [inline] — we go in the direction to link these together", Weber told motoring.com.au.

Featuring nominal 500 and 375cc modular cylinders, Mercedes' new four-cylinder turbocharged engines have already won praise in both petrol and diesel formats. Mercedes has further leveraged the technology, at least in petrol form, in a new generation of V8s.

The new engines will likely be used in C, E and S- Class vehicles plus some sporties and SUVs. The six will also be mated to hybrid drivetrains it seems.

The development of 2.2 and 3.0-litre sixes would leverage not only the part sets used in the brand's four-cylinder engines but would also make it possible for Mercedes-Benz to modularise expensive components such as intake and exhaust systems, the latter including catalytic convertors, diesel particulate filters and the like.

This would contribute to significant savings compared to V6 engines, Weber asserted.

And the move has other benefits up market. The latest Mercedes and AMG V8s are effectively two of the new fours on a common crankcase. Paired inline sixes would produce a modern, efficient V12 engine to replace the ageing existing 12-cylinder used in some AMG and Mercdes-Maybach models.

The argument against inline sixes in recent years has been packaging — in part, pedestrian safety. By definition inline sixes are longer than V6s and four-cylinder engines.

Weber hinted that this packaging change could be accommodated in the new MRA platform that will underpin the new E-Class and that will eventually anchor C and S-Class plus Benz's SUV segment counterparts.

"It's about managing complexity," Weber said.

"We look to a new vehicle which can go with synergies. There's a long way to go and the results count," the R&D boss stated.