German automaker Mercedes is set to lift the lid on its latest AMG model, the comfortable yet massively overpowered S 65 Cabriolet, at January’s motor show in Detroit. Basically, this is a soft-top with room for four to lounge in complete comfort or to go from 0-100km/h in a Porsche 911-obliterating 4.1 seconds.

This potentially dangerous turn of speed plus the tire-shredding 630hp on tap is thanks to a meticulously hand-constructed 6-liter biturbo engine, which is making its fifth and potentially most dramatic appearance in the current Mercedes-AMG range.

“The customer base for our V12 biturbo engine expects the ultimate in every respect. That is why we are offering a four-seater high-performance convertible with this legendary power unit for the first time. The new S 65 Cabriolet sets benchmarks for all relevant criteria: top performance, a breathtaking driving experience and exquisite appointments,” said Tobias Moers, Chairman of Mercedes-AMG GmbH.

However, this engine is being dropped in the S-Class and so the ferocity has to be balanced by formidable comfort and cutting-edge driving and safety tech. So, to ensure that passengers still feel cosseted whether the roof is up or down or no matter how far into the carpet the accelerator pedal is buried, the car has airmatic suspension for ironing out uneven asphalt.

It will also lean into or away from curves to improve cornering without spilling beverages, and has an impressively complex climate control system that deflects wind and unpleasant fumes out of the cabin with the roof down, blows warm air around occupants’ necks (called the airscarf) and heats armrests and other leather surfaces so there’s never a sense of wind chill.

Meanwhile touches that ensure the driver can unleash all 12 cylinders with confidence include a very smooth seven-speed automatic yet performance-oriented transmission, and a full head-up display to minimize distractions while optimizing the flow of information regarding speed, navigation and traffic sign recognition.

The full Distronic Plus suite of features are also on offer including lane monitoring and active lane keeping and blind spot monitoring, pre-collision braking – even at speeds of up to 100km/h – parking assist and cross traffic monitoring. Even if the car can’t avoid an accident, pre-collision systems will lock the brakes in the event of a potential rear-end shunt and pre-tension seatbelts.

The Mercedes-AMG S 65 Cabriolet will make its official debut in January at the North American International Auto Show and will go on sale in April 2016.