Mercedes-Benz is planning to enter the hot hatch market in 2012 with a 320bhp AMG-badged A-class.

The hot AMG version of the new, third-generation A-class will have a turbocharged 2.0-litre engine and four-wheel drive. It is being developed by Mercedes’ AMG performance arm under the direction of its new boss, Ola Källenius.

The hot A-class is due on sale in the UK in September 2012. It will be priced to compete with the Audi RS3, Volkswagen Golf R and an M Sport-badged, turbocharged four-cylinder version of BMW’s second-generation 1-series hatchback — which suggests that it could be around £35k.

The new A-class will be based on Mercedes’ MFA (Modularen Frontantriebs-Architektur) platform — a newly developed unitary construction structure that ditches the heavy and expensive ‘sandwich floor’ of today’s model.

Codenamed W176, the car is radically different from its tall predecessor. It takes on a much lower and more conventional two-box silhouette, overlaid with taut surfacing and styling cues first seen on the F800 Style concept car.

The racy new look will be previewed on a concept at next year’s Shanghai motor show. It is designed to attract a younger customer than today’s A-class.

The look will be further embellished on the AMG version by uniquely styled bumpers, pronounced sills, chromed tailpipes and 18-inch wheels. 

AMG had planned to use a 2.0-litre, direct injection engine running an electrically operated turbocharger from Swiss firm Hyprex. But concerns over its complexity and related production costs have forced a switch to a more conventional powerplant using a mechanical twin-scroll turbo.

Insiders with knowledge of the 2.0-litre, aluminium-block engine suggest that AMG’s powertrain department is aiming for a power output in excess of 300bhp. One source told us: “Something in the region of 320bhp is realistically possible with the technology at hand.”

By providing the car with a new six-speed, dual-clutch gearbox and a Haldex-style four-wheel drive system with a multi-plate clutch, Mercedes is hoping to dispel any concerns about traction. But in a bid to provide the A-class AMG with the dynamics to match its badge, the new driveline will feature a positive rear-drive bias, together with an electronically operated torque-vectoring clutch to juggle drive between each of the rear wheels.

Although the AMG is likely to grab much of the attention surrounding Mercedes’ future entry-level model, standard versions of the A-class will also get new engines.

Today’s 1.5-litre, 1.7-litre and 2.0-litre petrol and 2.0-litre diesel four-cylinder engines are on their way out, because they are unsuitable for the non-sandwich platform.

In their place, Mercedes plans to use a combination of existing in-house units and new small-capacity engines from alliance partner Renault. Over time, the line-up will eventually include turbocharged 1.2-litre, 1.4-litre and 1.8-litre direct injection petrol engines, along with 1.6-litre and 2.2-litre common-rail turbodiesels.

All of the new powerplants will come, as standard, with automatic stop-start and brake energy recuperation systems as part of Mercedes’ BlueEfficiency programme.