Mercedes-Benz inline six dawns

Mercedes-Benz has confirmed it is introducing two electrified engines as part of the standard S-Class limousine range.

And the big news is that these new engines are straight sixes for the first time in something like two decades of Benz engine development. The new 3.0-litre inline six-cylinder turbo-petrol engines, codenamed M256, will power S 450 and S 500 variants, producing 270kW/500Nm and 320kW/520Nm respectively.

Using less fuel and emitting fewer toxic emissions, the new S 500 engine pumps out more power via the inclusion of a 48-volt electrical system, 1kWh lithium-ion battery and electrically-driven turbochargers. A beefy starter/alternator is also used and can boost output by 16kW and 250Nm, Benz claims.

Fuel efficiency and CO2 outputs for the two new engines are commendable, rated at 6.6L/100km and 150g/km for both.

Mercedes says the new S 500 is 22 per cent more efficient than the old S 500 and the advanced six-cylinder powerplants will slot under the bonnet of the new-look vehicle, which features revised bumpers, grille and air dams, for a subtle visual refresh.

The revamped S-Class also gains enhanced semi-automated driving prowess with more sensors and improved software, but the autonomous corner control that relies on detailed maps to pre-empt routing is unlikely to be offered in Australia.

However, the new S-Class can change lanes by itself with a tap of the indicator stalk, a la Tesla Model S and Benz E-Class. Its Road Surface Scan technology that adjusts the suspension for "magic carpet" ride comfort has also been updated.

When Mercedes-Benz first revealed the facelifted 2017 S-Class in April at the Shanghai motor show it confirmed the new 3.0-litre turbo-diesel engines in the S 350d and S 400d models, pumping out 210kW/600Nm and 250kW/700Nm respectively.

But all eyes will be on the new turbo-petrol 3.0-litre sixes, which are expected to power around half the models in the Mercedes-Benz range.

AMG has made no secret of its desire to offer a hard core version the new inline six, which is tipped to eventually replace the current 3.0-litre V6 AMG "43" models. The top-end V8 models are expected to continue.

The electrified S 450 and S 500 inline six-cylinder vehicles will be joined by eight and 12-cylinder variants of the S-Class too, including the S 560 powered by a 4.0-litre twin-turbo V8 and the big-daddy S 65 AMG, propelled by a haughty 6.0-litre twin-turbo V12 with 463kW and 1000Nm.

There will also be an S 600 with 390kW and 830Nm generated from its turbo 12-cylinder engine.

Despite escalating emissions targets that are slowly killing some high-performance engines, the V12 engine will not be axed, Mercedes insists. Expect a similar 48-volt electrification system to the six-cylinder petrol engines and possibly a mild hybrid system for future engine revisions.

Mercedes-Benz Australia has not yet said which engines will be offered locally but the S 500 is tipped to be a starter.

The updated S-Class is due in Australian showrooms late in 2017 after its October launch in Europe, but stay tuned for our first test of the new model on Tuesday July 25.