Mercedes GLA45 AMG hauls in the world’s most powerful four cylinders

With the 2015 GLA-Class small crossover SUV, Mercedes sought to bring its style and cache to a wider audience, much like the German automaker did with its CLA-Class. This meant front-wheel drive as standard with more plastics, less speed and (arguably) better value. It became a Mercedes-Benz with an asterisk, at least in the eyes of some.

But then Mercedes sent its soft-road machine to AMG, where it took on a bigger engine, racier bodywork and a tauter suspension. It's no longer weakened; it's a monster. And yet — if it's anything like the CLA45 AMG — it should sticker at a reasonable price.

Enter the 2015 Mercedes-Benz GLA45 AMG, featuring the most powerful mass-production four-cylinder engine in the world.

With 355 hp and 332 lb.-ft. of torque, the GLA45 AMG should be good for a 0-60 mph run of 4.8 seconds. That power is now routed through Mercedes' AMG 4MATIC four-wheel drive system, and while it's still effectively a front-wheel drive car, it splits torque 50:50 when needed. A 7-speed DCT transmission promises lightning-quick shifts, and launch control comes as standard.

But that engine. Let's talk about that some more.

It's a 2.0-liter turbo, which the mathematicians in the room will see gives it a ratio of 178 hp per liter. Putting that into perspective, the insane 662-hp Shelby GT500 has a ratio of 114 hp/liter; the Porsche 911 Turbo S manages 147 hp/liter. So AMG's lump is pretty impressive, and sees rounds in the CLA45 AMG as well as the A45 AMG hot hatch we don't get.

More on that forbidden fruit. The GLA45 is remarkably similar to the A45. It's just more pudgy and boasts a little more interior room for a market that yearns for such a thing. You'd be forgiven for calling it a hatchback, as it's as hatchy as a CUV can be. And that's a good thing. Pricing isn't yet available, but like the CLA45's starting cost of $47,450, it promises ludicrous fun at a levelheaded price.