Mercedes-AMG will launch its new 2.0-liter turbo four in a handful of AMG 45-badged models in the very near future and has suggested that it could get more powerful.
The M139, as it is code-named, has already been officially confirmed with a peak output of 415 hp and 369 lb-ft (500 Nm) of torque. Power per liter sits at an impressive 208 hp, making this the most powerful mass-production four-cylinder road car engine ever.
Compared to the M133 that powered the previous-gen AMG 45, the M139 has been flipped 180 degrees, with the turbocharger and exhaust manifold now facing backwards. The turbo also features roller bearings and the engine incorporates an improved exhaust manifold helping to prevent individual cylinders from negatively influencing one another during load cycles, while it runs on 0W20 oil (!) and still needs servicing every 20,000 miles or once a year, whatever comes first.
Producing a turbocharged four-cylinder engine with so much power is an impressive feat, made possible by numerous upgrades that range from new oil- and water-cooling systems to forged aluminum pistons and an ultra-strong crankcase, but Affalterbach’s engineers don’t appear finished with this powertrain.
“There will be more to come. There’s always room for improvement. But 421 PS is really quite a high number, especially when it’s also street-legal. That was the challenge. We’ll see what the future will bring,” he said.
If AMG does boost horsepower and torque figures from this engine, we could end up with some very exciting performance cars. And to think that a blue-blood supercar of the early 2000s, like, theFFerrari 360 Modena, had “only” 395 horses at its disposal (and less torque) – and, from what we recall, was ferociously fast.