• Most powerful four-cylinder engine in the world
• Has the edge over its Audi and BMW rivals
• Set to arrive in the UK in July

The new Mercedes-Benz A45 AMG has been announced ahead of its world debut at the Geneva Motor Show in March. It will be the proud possessor of the most powerful four-cylinder production engine in the world – significantly more potent than its BMW M135i and Audi RS3 rivals.

From the outside, the A45 gets all the usual AMG addenda over and above the standard A-Class. Side skirts, a deeper front valance, larger, sportier alloys, twin chrome tail pipes and more muscular wheelarches are the signature AMG styling details. Red brake callipers and a roof-mounted spoiler complete the performance make-over.

Inside, the car gets black man-made leather sports seats with contrasting red stitching and a similar treatment on the steering wheel, which also features paddles to change gear with. Red is a familiar theme throughout the cabin, with scarlet seat belts and the air vents trimmed with red plastic. The dashboard also comes with carbon-fibre look trim.

The engine is likely to be the headline-grabber with this car – a 355bhp turbocharged four-cylinder unit (the first ever four-cylinder AMG engine) which produces 332lb/ft of torque yet still manages to return 40.9mpg and emit 161g/km of CO2. Compare this to the 335bhp Audi RS3, the 320bhp BMW M135i and even the 350bhp Porsche 911 and it shows how far ahead of its rivals the A45 is. This volcanic power will be directed to all four wheels via a seven-speed dual-clutch transmission. The A45 will accelerate from 0 to 62mph in 4.6 seconds and on to an electronically limited top speed of 155mph.

As well as using the 4MATIC all-wheel drive system to keep the power in check, the A45 AMG also has uprated brakes, suspension and tyres over the standard A-Class.

The A45 AMG will be shown at Geneva alongside its CLA45 AMG stablemate and the car should arrive in the UK sometime in July this year. Pricing and UK specification will be announced at the Geneva Show.

By James Richardson

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