It is now almost half a century since a couple of Mercedes engineers decided to quit making cars and start making race engines instead.

Thus AMG was born. The firm soon branched out into unofficial performance mods for Mercedes’ road-going models, eventually joining forces with Mercedes to make the first factory-approved AMG model in the mid-1990s: the W202-generation C 36 AMG.

It was a marriage that would only ever lead in one direction. Mercedes parent DaimlerChrysler acquired a controlling interest in AMG in 1999 and the remainder of the company’s shares six years later, turning AMG into the wholly owned performance subsidiary we know today.

And what a busy outfit it has become, expanding from an output of vehicles believed to have numbered fewer than 10,000 units a year midway though the previous decade to more than 50,000 units a year now.

Mercedes-AMG, as it has become known, isn’t stopping there. Having ushered in some big-selling turbo four-cylinder models over the past three years, it’s now adding a range of turbo V6 options to sell alongside its range of full-fat ‘63’-labelled turbo V8s.

The first of them is this SLC 43.

The new top-of-the-line roadster has been introduced as part of a mid-life facelift for the car previously known as the SLK that, alongside the identity change, brings exterior styling tweaks, new cabin equipment and changes to the suspension, gearbox and engine line-up.

In the UK, the range now consists almost entirely of four-cylinder models, running through 181bhp SLC 200, 201bhp SLC 250d and 242bhp SLC 300 until you reach the 362bhp V6 SLC 43.

So will swapping eight naturally aspirated cylinders for six force-fed ones suit a car tasked with perfectly splitting the difference between a cruising and a sporting brief?

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