We’ve had an idea that the Audi RS 7 Sportback would be heading to the United States for a while now, but Audi has finally delivered confirmation. As part of an RS model expansion, Audi’s fastest four-door coupe is making its debut at this week’s Detroit Auto Show.

While the RS 7 shares the same basic twin-turbo, 4.0-liter V-8 engine with the Audi S8, output is increased to 560 horsepower and 516 pound-feet of torque, a gain of 40 horsepower and 35 pound-feet of torque over the S8.

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 OF THE 2014 AUDI RS 7.

Thanks to the engine’s exhaust routing (inside the cylinder banks, where the turbos are located), the turbos spool up very quickly to virtually eliminate lag. While peak power comes between 5,700 and 6,700 rpm, peak torque is available from just 1,750 rpm.

An eight-speed Tiptronic transmission sends torque to the standard quattro all-wheel drive, and the RS  7 is capable of delivering a run from 0-100 km/h (62 mph) in just 3.9 seconds. Top speed is electronically limited to 155 mph, although a “Dynamic Package” can raise this to 174 mph and a “Dynamic Package Plus” can increase it to 190 mph.

Despite the RS 7’s impressive performance, Audi says the car can return fuel economy numbers (in European cycle testing) of up to 24 mpg. It achieves this via the use of start/stop technology and cylinder deactivation, something Audi calls “Cylinder on Demand” (COD).

At low to medium engine speeds, cylinders 2, 3, 5 and 8 are deactivated via electromechanical valve actuators. To ensure that the engine remains virtually vibration-free on four-cylinders, Audi employs active engine bearings to produce vibration-canceling, out-of-phase counter-oscillations.

Customers can choose from an air suspension that lowers ride height by 0.79 inches at speed and includes adaptive damping for the ultimate in ride control, or a more conventional sport suspension that uses steel springs and linked, three-stage adjustable dampers.

Standard 20-inch forged aluminum wheels cover 15.35-inch front brake rotors, clamped by six-piston calipers. If you’re the “more is better” type, you can opt for 21-inch cast wheels and even carbon-ceramic brake rotors. Standard brakes are available with either black or red calipers, while carbon-ceramic binders get gray calipers.

To save weight, the RS 7’s body is built from a mix of aluminum, high-strength steel and ultra-high-strength steel. Setting it apart from the S7, the RS 7 wears unique front and rear bumpers, a gloss black honeycomb grille, a power-extending rear spoiler, a rear diffuser and elliptical tailpipes.

Ten exterior colors are available, including the optional matte finish Daytona Gray. Available matte aluminum and carbon styling packages allow for further personalization, and carbon package cars get a restyled front splitter and diffuser. Carbon fiber mirror caps are also an available option.

Inside, sport seats are wrapped in black Alcantara and leather, stitched in a diamond-quilted pattern. If you’d prefer solid leather, honeycomb-quilted Valcona leather (in black or silver) is an available option, and a black or silver Alcantara headliner can be ordered to match.

Audi RS 7 Sportback

Audi RS 7 Sportback

Carbon fiber trim is standard in the cabin, though other materials are available if the buyer prefers. If you’re not fond of the options Audi has listed on its build sheet, further personalization is available through the Audi Exclusive Program.

As you’d expect of a car positioned atop Audi’s range, the list of standard features is lengthy, including such things as HID headlights, Audi’s parking system plus, tri-zone climate control and an Audi-developed audio system. Key options include a heads-up display, a comfort package, a Bang & Olufsen audio system and the previously-mentioned Dynamic and Dynamic Plus packages.

We’ll bring you details on pricing and availability closer to the RS 7’s launch later in the year, where it will most likely arrive as a 2014 model.

For more news and product introductions from the 2013 Detroit Auto Show, bookmark our dedicated show page.