The CLA 45 can reach 62 mph from a stop in 4.2 seconds.

Mercedes-AMG has upgraded the CLA 45 and the GLA 45 (pictured) with a new, more powerful engine that debuted late last month under the hood of the A-Class.Both compacts benefit from a turbocharged 2.0-liter four-cylinder engine that makes 381 horsepower - about 20 more than the mill that powers the outgoing model - at 6,000 rpm and 350 lb-ft. of torque from 2,250 to 5,000 rpm. Built entirely by hand, the turbo four boasts an impressive output of 191 horsepower per liter of displacement.

The four-banger sends power to all four wheels through a seven-speed dual-clutch automatic transmission that has been revised with shorter gear ratios, an update that noticeably improves acceleration. As a result, the CLA 45 can reach 62 mph from a stop in 4.2 seconds, the CLA 45 Shooting Brake performs the same task in 4.3 seconds and the GLA 45 takes 4.4 seconds. To put those figures into perspective, the 355-horsepower CLA 45 took 4.6 seconds to hit 62 mph.

A switch on the center console lets the driver choose one of four driving modes called Comfort, Sport, Sport+ and Race, respectively. Additionally, buyers can select the newly-available AMG Dynamic Plus package, which bundles a long list of handling-focused features including a mechanical locking differential on the front axle.

All three models are on sale now across Europe. In Germany, the CLA 45 carries a base price of €56,673 (about $62,500), the Shooting Brake starts at €57,268 (roughly $63,000) and the GLA 45 stickers for €56,168 (approximately $68,800). Pricing information for the U.S.-spec AMG-tuned compacts will be published in the next few weeks.

Photos by Drew Johnson.