BMW debuted the X4 M40i next to the M2 Coupe in Detroit, marking the launch of their smallest coupe-SUV in the US market.

A coupe-SUV or SAC (Sports Activity Coupe) as BMW likes to call these type of vehicles, the X4 M40i represents the fastest, more performance-oriented version of the X4. The range-topper uses the single turbo straight six 3.0-litre of the company, tuned to make 355hp between 5,800 and 6,000rpm and 343lb ft of torque.

Combine this power with the intelligent xDrive AWD system and the fast-changing eight-speed automatic gearbox and you get a zero to 60mph time in just 4.7 seconds, a best-in-class figure. Top speed is electronically limited to 155mph.

Compared to its lesser relatives, the X4 M40i is set up with an increased camber up front, with strengthened wishbones for better steering feedback and increased response. A set of stiffer springs and reinforced stabilizers on both axles further optimize driving dynamics and reduce body roll while BMW has installed a variable-ratio steering rack.

The starting price for the BMW X4 M40i is set at $57,800 plus destination and handling fees. If you wanted the fastest middle-size SUV with a sloping roofline, this might just do the trick.

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