Audi is following in the footsteps of BMW’s M3/M4, ditching the previous RS4’s natural aspirated V8 in favor of a force-fed six-cylinder engine, albeit with an electric twist, for its new high-po model.

Reports coming in from Germany say that Audi’s Quattro division will pair a modified version of the current S4’s 3.0-liter V6 with a small electric turbocharger providing instant boost at low rpm and a conventional exhaust gas-driven turbocharger for high-end performance.

The electric turbocharger will be powered by batteries that are recharged from a generator recovering lost energy under braking, completely eliminating lag and greatly boosting low-speed performance, with the added benefit of being simpler than traditional twin-turbo setups. As soon as the system detects high enough exhaust pressure, the regular turbo kicks in.

Besides providing a more linear performance without any lag, the electric turbo setup also promises to improve CO2 emissions.

The new powertrain is expected to push out somewhere between 480 and 500 horsepower in the RS4, a considerable increase over the previous B8 RS4’s 444bhp (450PS) 4.2-liter V8. Audi’s quattro all-wheel drive system with asymmetric rear-biased torque split will come as standard, and will likely be paired exclusively to dual-clutch automatic transmission.

As evidenced by the attached fender extensions, the RS4 Avant you see here is an S4-based test mule, although one that incorporates a differ front bumper with larger air ducts along with bigger wheels and brake discs, and RS-style oval pipes at the back.

In its final form, the RS4 Avant will have distinct flared fenders on all four corners together with some other key differences over the S4 such as a unique grille, a more aggressive front spoiler and intake treatment in line with other RS cars. Interior upgrades will include sportier trim accents and model-specific front seats, steering wheel and instrument panel.

The RS4 Avant should make its first public appearance at the Paris Motor Show in early October, with a sedan body style to follow.

Photo Credits: CarPix for CarScoops

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