The production version of the new Mercedes-Benz GLA45 AMG will debut in Detroit next week.

Mercedes-Benz has set out to rewrite the rules on small, entry-level luxury cars.  Forget the little C-Coupe of a decade back, and the original Baby Benz.  The maker is out to prove that good things can come in small packages – and with the upcoming introduction of the new Mercedes-Benz GLA45 AMG, add the word, “powerful” to your list of superlatives.

The production version of the new Benz crossover’s most powerful model will make its official debut at the North American International Auto Show next week, but Mercedes is offering up an advanced look at the 355-horsepower compact crossover.

Based on the same basic “architecture” as the new Mercedes CLA coupe-like sedan, the GLA is taking aim at Gen-X and Millennial buyers who put a premium on luxury brands but might otherwise be stuck in a more mainstream segment.  The AMG version, meanwhile, is the most affordable high-performance crossover the Teutonic maker has ever offered.

Mercedes claims this turbo 2.0-liter is the most powerful series production I-4 in the industry.

It also happens to boast the most powerful four-cylinder engine ever put into a “series” production vehicle, Mercedes claims.  In U.S. spec – which loses about 5 hp versus the European edition – the GLA45 AMG can nonetheless launch from 0 to 100 kmh (0 to 62.5 mph) in a mere 4.8 seconds, on its way to a 250 kmh (155 mph) top speed.

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At 332 lb-ft of torque through a seven-speed transmission linked to all four wheels, the 2.0-liter turbocharged engine features a sand-cast, all-aluminum crankcase, forged steel crankshaft and pistons, and uses various technologies to reduce internal friction.

It also boasts Stop/Start capability, the engine briefly shutting down at a light or when idling on line then automatically starting up when the driver’s foot lifts off the brake.  In European trim, that is expected to help the new crossover deliver about 32 miles per gallon – though Mercedes isn’t revealing U.S. fuel economy numbers yet.

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While the turbo I-4 is the powerful heart of the new GLA45 AMG, but as you’d expect, the top-line edition has plenty more going for it.

Inside the new GLA45 AMG.

The performance model features a number of design details intended to both improve aerodynamics and give the GLA45 a more muscular appearance. That includes the front splitter with AMG “twin blade radiator grille, both in matte titanium grey paint.  There are oversized cooling air intakes and bi-xenon headlamps are standard equipment. The rear of the GLA45 AMG features a diffuser insert and rectangular, chrome-plated twin tailpipes.

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A special series of upgrades includes mirror housings and other components made of carbon-fiber, as well as a rear spoiler and red-painted brake calipers.

Inside the AMG edition comes standard with a unique set of sport seats, 3-spoke nappa leather-covered steering wheel with paddle shifter, an AMG instrument cluster and brushed aluminum accents.

Mercedes isn’t saying what the GLA45 AMG will go for yet but if the CLA is any example, the price premium will be stiff.  The base CLA250 starts at a modest $29,900 while the high-line CLA45 AMG starts at $47,450.  Expect a similar gap for the GLA45 AMG over the base crossover.