2020 Mercedes-AMG CLA 45 has the world's most powerful four-cylinder

We may not get its strongest variant, though.

Mercedes-Benz again expanded the second-generation CLA line-up with a little bit of help from its performance-oriented AMG division. The company revealed a pair of range-topping models named CLA 45 and CLA 45 S, respectively, though it sounds like only the former will be sold in the United States.

Both 45s are powered by the same turbocharged, 2.0-liter four-cylinder engine. Presented as the most powerful series-produced four-cylinder engine in the world, it makes 382 horsepower at 6,500 rpm and 354 pound-feet of torque from 4,750 to 5,000 rpm in the CLA 45. Selecting the S model bumps those figures to 421 and 368, respectively. That's a lot to ask from a two liters of displacement.

Its output reaches the pavement via an eight-speed automatic transmission and Mercedes-Benz's 4Matic all-wheel drive system. The optional drift mode lets drivers get sideways by sending 100% of the engine's torque to the rear axle.

The 40 additional horses don't have a huge effect on straight-line performance. The CLA 45 takes four seconds flat to reach 60 mph from a stop, while the CLA 45 S lowers that time by merely a tenth of a second. Top speed checks in at 155 mph and 167 mph respectively, though both are electronically limited. The 45 can keep up with the 45 S all the way to 167 when it's fitted with the optional driver's package.

The images released by Mercedes show the European-spec version of the CLA 45 S. It receives a deeper front bumper with bigger air vents, AMG's familiar Panamericana grille characterized by vertical slats, and winglets on either side of the bumper. Out back, a trunk lid-mounted spoiler and a wide diffuser surrounded by four oval exhaust tips help the 45 stand out from the regular CLA.

Here's where the plot gets confusing: there's no indication the CLA 45 S will be sold in the United States. Mercedes has nothing to announce about the 421-horsepower model, according to CNET's Roadshow. That means what you see in our gallery isn't necessarily what you'll get when the 45 arrives in showrooms in late 2019. We don't expect the visual difference between the two models will be huge, though.

The entry-level CLA 250 and the mid-range CLA 35 will both begin appearing on dealer lots at the same time as the CLA 45. Pricing information for the 2020 CLA line-up will be revealed in the coming months.

What's next?

The turbocharged, 2.0-liter four found under the CLA's hood will power other 45-badged Mercedes compact models. The German firm already revealed the A45, which is a Volkswagen Golf-sized hatchback developed largely for the European market. We expect the GLA 45 crossover will return, and the three-row 2020 GLB could offer the same engine to cater to families in a hurry. Whether the A-Class sedan will spawn a range-topping 45-badged model remains to be seen, though.