With up to 421 hp and 500 Nm of torque from just 2.0 litres of displacement, the new M139 turbocharged four-cylinder engine in the latest Mercedes-AMG A 45 and CLA 45 is an impressive piece of engineering. But having spent so much time and effort to extract these headline figures, surely it would be a waste to confine it to Stuttgart’s smallest models, wouldn’t it?

Apparently Affalterbach feels the same way. Speaking to us at the Frankfurt Motor Show, AMG boss Tobias Moers confirmed that the engine won’t be limited to transverse applications. “The reason [why it makes so much power] is that we’re going to use that engine for further applications which are not necessarily east-west applications,” he said with a knowing smile.

This means that the engine has been developed for longitudinal use as well, opening the door for its implementation in larger rear-wheel drive models. The possibilities are endless, though don’t expect a C 45 to appear anytime soon.

The company makes no secret about the fact that it is heading down the path of electrification, with next-generation models set to feature hybrid powertrains. The M139, then, could play a big part of this push – augmented with a powerful electric motor, it may well make its way into AMG’s mid-tier 43 and 53 models, replacing their six-cylinder engines.

Moers added that the power outputs of future 63 models like the E 63 will likely continue to hover around the 600 hp mark even with the use of more powerful hybrid systems. As such, these cars will probably feature smaller, less potent engines compared to the thundering 4.0 litre twin-turbo V8 currently being utilised.

Whatever it is, we won’t have to wait long before we’ll see the direction AMG will take for its future. Daimler chairman Ola Källenius told us the company will show “some ideas” for the brand later this year.

GALLERY: Mercedes-AMG A 45 S 4Matic+ and CLA 45 S 4Matic+