Mercedes-Benz CLA AMG packs a lot of punch in a little package

NEW YORK--The all-new CLA-class is not even out in the showrooms yet, but Mercedes-Benz already unveiled an AMG version, a sport-tuned model boasting the highest output four-cylinder engine in production. The new CLA-class is Mercedes-Benz's smallest model in the U.S., and competes against other compact luxury cars, such as the BMW 1-series.

The star of the CLA AMG, as with other AMG vehicles, is the engine. Turbo badges on the fenders refer to the turbocharged direct injection 2-liter four cylinder engine under the hood, which outputs a whopping 355 horsepower and 332 pound-feet of torque. Much of this power comes courtesy of a twin scroll turbo generating as much as 26 PSI. A turbo of this size should lead to turbo lag, but Mercedes-Benz says the twin scroll architecture creates quick acceleration from low revs.

The CLA came out with front-wheel-drive architecture, but each AMG model will have Mercedes-Benz's 4Matic all-wheel-drive system. Using vehicle sensors for speed and steering, the 4Matic system can move up to 50 percent of available torque to the rear wheels to aid handling. There is no torque vectoring across the front or rear axle, but Mercedes-Benz incorporated something it calls Curve Dynamic Assist into the electronic stability program, which will apply braking at individual wheels to help the car corner.

Many of the amenities found on the standard CLA, such as this glass roof, also make their way to the AMG model.

The CLA AMG uses a fixed, sport-tuned suspension, but the driver will be able to choose between Sport and Comfort modes, affecting the engine and transmission. Pushing the electronic stability program (ESP) button once engages a sport mode, dialing back the stability program, while holding it down completely disengages it. However, ESP temporarily becomes fully active whenever the driver hits the brakes, no matter which mode the car is in.

The CLA AMG gets custom interior options, such as carbon-fiber trim pieces. Along with the cabin electronics from the CLA-class, the CLA AMG adds a performance computer with a lap timer.

Connecting the engine to the all-wheel-drive system is a seven-speed, dual-clutch transmission. In Sport mode, it maintains high engine speed and downshifts dynamically, based on driving style. It allows sequential manual shifts, using paddles on the steering wheel, under full throttle. The transmission also enables launch control, helping the CLA AMG hit 60 mph in 4.5 seconds.

The shift paddles use a typical configuration, downshifting on the left and up on the right. The electrical power-steering system dials back boost as speed increases, but does not change ratio.