Crank up that boost!
Normally, you would associate small, 2.0-liter four-cylinder engines with efficiency, not performance. Even when they are turbocharged, as so many are these days, the goal is to replace the need for a big, thirsty V6. Right? Based on the latest engine to emerge from the engineers at AMG, Mercedes-Benz would beg to differ. Enter the hand-built M 139 engine, what Mercedes-AMG claims is the most powerful four-cylinder engine in the world.
At full tilt, this 2.0-liter engine produces a whopping 416 horsepower and 369 lb-ft of torque. Normally, talking about a new 2.0-liter engine would not be that impressive. Most units in ordinary cars these days make around 240 horsepower and 260 lb-ft of torque. In fact, I marvel at just how many of those engines make 258 lb-ft of torque, as if that’s the universe saying that’s the best possible output.
This, though, cranks both those figures up to eleven. Going through the specs, one number that immediately stood out to me on the so-called “S-model” variant of the M 139 unit is the maximum charge pressure: 2.1 bar. That amounts to 30.45 pounds per square inch (psi), which struck me as a hell of a lot of pressure for a turbocharged gas engine. Mind you, the engine has been designed to handle that. It wasn’t long ago, though, that even performance motors only ran with about half that much boost.
The “base” version only makes slightly less horsepower
With that sort of pressure, this engine makes its 416 horsepower with a single twin-scroll turbocharger. Mercedes is keen to point out that this also makes the M 139 one of the most power-dense engines in current production. In fact, it makes 208 horsepower per liter.
The engine does have a “base” variant as well, that makes 382 horsepower and 369 lb-ft of torque. Can I just point out that an early 2000s Mercedes-Benz C600 managed 362 horsepower and 391 lb-ft of torque? And that was from a massive 6.0-liter V12.
The new M 139 engine will make its way into the revised CLA 45 model, as well as the GLA 45 crossover and A 45 sedan. It will definitely be a step up from the old version’s 375 horsepower and 350 lb-ft of torque.
Correction 6/7/19: I (incorrectly) stated that this engine was not making its way into any particular car yet. It will make its way into the Mercedes-AMG CLA 45, GLA 45 and A 45. Apologies for the error!
Speaking of AMG, check out one of their latest offerings below: