Mercedes-Benz debuts new hybrid straight-six

S450 and S500 will get hybrid in-line engines which match the older V8s’ outputs

2018 Mercedes Benz and AMG S Class to feature hybrid straight six

Mercedes-Benz has confirmed that the 2018 S-Class will be the first to receive the new electrified straight six which has been so-far revealed to achieve an output of 320kW.

And, as far as downsizing engines goes, that’s good news for the S500.

With the previous V8-powered S500 boasting outputs of 335kW/700Nm, the six-pot S-Class will surely keep up. Though its 520Nm is substantially weaker, the S-Class has learned a new trick.

2018 Mercedes-Benz S-Class frontIn the S500, the in-line six will be able to add an extra 250Nm of torque and 16kW via the single-unit “integral starter/alternator” when it’s needed. This brings total figures up to 336kW/770Nm, which pips the V8’s numbers by 1kW/70Nm.

The engine is also slated to be used in the S450, which will be tuned to a more modest output of 270kW/500Nm.

As reported by MOTOR’s sister publication Wheels, the new straight six will also be plonked into the upcoming Mercedes-AMG CLS53.

In its CLS home, the in-line six will produce 320kW and more torque than it does in the S500, though will be given an extra 50kW from the electric system when called to action with a nudge of the right foot.

2018 Mercedes-Benz S-Class side profileWhat’s most impressive about the new engine is that while it retains the performance credentials of the V8 it’s replacing, M-B says it also keeps estimated fuel usage to a manageable 6.6-7.0 l/100km for both the S450 and S500.

Mercedes-Benz has adopted a new battery system to achieve this and, though we’d expect a 48-volt system as-per the Audi SQ7, M-B’s official statement calls it a 49-volt system. Typo? Possibly.

As for the next targets for this new hybrid straight-six, the upper echelon of the S-Class (including the 6.0-litre V12 AMG S 65) are unlikely to see its use, though how soon we’ll start seeing other V6s dropping out of use is yet to be confirmed.


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