Mercedes-AMG will send a clear message that it is adapting to modern demands with the upcoming third-generation C63 by forgoing its long-standing V8 power in favour of an advanced four-cylinder hybrid drivetrain that develops more than 500bhp.
The four-wheel-drive rival to the Audi RS4 and BMW M3 is already undergoing intensive development at AMG’s Affalterbach engineering headquarters. The first sighting of a camouflaged prototype shows off an evolutionary look in line with the recently facelifted E-Class, and suggests AMG will not tone down the saloon's aggressive styling as it downsizes the engine.
The potent four-cylinder engine kicks out a maximum of 416bhp and 369lb ft of torque in non-electrified form in the new A45 and its related siblings. The unit has already been engineered for longitudinal mounting as well as mild-hybrid electric boosting. It’s destined to be used in not only the next C63 but also, in a less heavily tuned form, in a follow-up to today’s turbocharged 3.0-litre V6-powered C43.
The new C63 will be offered in saloon, coupé and convertible bodystyles, with the next C43 likely to be sold in those three guises as well as an estate version.
Autocar has been told the M139 engine will adopt a 48V integrated starter motor similar to that already used by the turbocharged 3.0-litre in-line six-cylinder M256 unit, which powers the CLS 53 4Matic+ and other recent new AMG models.
In the CLS 53 4Matic+, the gearbox-mounted starter motor provides an additional 22bhp and 184lb ft of electric boosting. In the next C63, however, it is set to be tuned to provide significantly more power in combination with a similar torque loading.