Most powerful road-legal Mustang makes its debut in Detroit, featuring a gaping new snout.

Ford has unveiled the Mustang Shelby GT500 at the 2019 Detroit motor show, finally un-caging the meanest, maddest production pony (or should that be snake?) ever to grace public roads.

The Shelby GT500 is powered by a hand-built 5.2-litre V8 engine with a 2.65-litre Roots-type supercharger nestled within the vee. Said to crank out roughly 522kW of power, or 700hp in the old money, Ford is billing the GT500 as the most powerful road-legal Mustang ever.

Hooked up to a carbon-fibre driveshaft and a seven-speed Tremec dual-clutch transmission, the GT500 will have a 0-60mph (0-97km/h) time of around 3.5 seconds, and a standing quarter mile (400m) time under 11 seconds.

With wider front wheel arches, the GT500 rides on 20-inch wheels with Michelin Pilot Sport 4S tyres at both ends, and standard magneto-rheological suspension.

A Handling Package adds adjustable strut top mounts and a spoiler with a Gurney flap. A range-topping Carbon-fibre Track Package includes exposed carbon-fibre wheels, Michelin Pilot Sport Cup 2 tyres, slightly wider rear wheels, adjustable wing and splitters, and deleted rear seats.

In addition to its wider stance, the GT500 is easily distinguished from lesser Mustangs thanks to its more aggressive front end, and at the back there's a standard spoiler and new composite materials for the diffuser.

The larger grille and duct openings, as well as the six heat exchangers, are said to increase cooling pack airflow by over 50 per cent. The bonnet includes a large 79-by-71cm louvred vent with a removable aluminium rain tray for both improved heat extraction and more downforce.

Inside the cabin, the Shelby GT500 features a 12.0-inch instrumentation screen, exposed carbon-fibre highlights on the dashboard, suede trim for the door panels, and a Sync 3 infotainment system with an 8.0-inch touchscreen.

Options include Recaro racing seats, 12-speaker B&O Play sound system, and powered seats with suede inserts.

The Ford Mustang Shelby GT500 will go on sale in the US from the third quarter of 2019.