Although we’re generally remarkably impressed with the inherent efficiency of modern forced-induction motor, why is it that we welcome the 5.5-litre, twin-turbocharged motor in the CLS 63 S with a mild sense of trepidation? 

Mainly because we’ve been so won over by the depth of character and performance of the naturally aspirated 6.2-litre V8 it replaces. However, this engine not only has more grunt than the 6.2-litre V8 but is also 32 percent more efficient.

And in no installation does it make more sense than in the CLS. We already know the four-dour coupé to be excellent luxury transport or for those craving extra practicality a shooting brake, and as a sort of high-end enthusiast’s limo it can justify having 576bhp better than most other Mercedes

But there’s no point to having such extravagant outputs – or an equally extravagent price – if it’s not sensationally entertaining, as well as civilised executive transport. And that’s not an easily achieved compromise.

In 2014, the Mercedes-Benz CLS was given a facelift, which largely was condensed to a new front grille, bumper and headlights, while the inside was given a light sprucing up. The CLS 63 S gained a wet clutch version of its seven-speed automatic as AMG seeked faster shifting to help unlock its performance potential.

Save money on your car insurance

Compare quotesCompare insurance quotes

First drives

Find an Autocar car review

Driven this week

  • BMW X3
    Car review
    19 January 2018
    The stakes have never been higher for BMW’s mid-sized SUV, now the X3 in its third generation. So can it deliver?
  • Nissan Leaf
    First Drive
    19 January 2018
    Better looks, better value, better range, stronger performance and a quiet and relaxing drive make the Nissan Leaf a leading EV contender again
  • Volkswagen Up GTI
    First Drive
    18 January 2018
    Funky, light, enjoyable and even reasonably priced, the Volkswagen Up GTI is a car to be appreciated on its own compelling terms
  • Skoda Fabia 1.0 TSI 110 Redline
    First Drive
    18 January 2018
    Our first flavour of the 1.0 TSI-engined Skoda Fabia on UK roads shows it’s versatile but not all that sporty
  • Ford Ecosport 1.0 Ecoboost 125 Zetec front
    First Drive
    18 January 2018
    Can the updated Ford Ecosport improve its reputation and become the small SUV of choice, or is it another misguided effort from the Blue Oval?