According to a report from Australia's Motoring, the 2017 Subaru WRX STI will adopt a plug-in hybrid powertrain with an electric motor-driven all-wheel-drive system.

The report cites an unnamed source that indicates Subaru's famous all-wheel-drive system will switch to a new layout that employs an electric motor mounted to the rear axle. Powering the front wheels will be a revised version of the 2.0-liter turbocharged four-cylinder currently used in the standard WRX. Our guess is the updated engine is the one we sampled in the WRX STI prototype we drove around Suzuka Circuit, churning out well over 300 hp.

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Motoring predicts 320 hp from the new powertrain--a 15-hp leap from the current Subaru WRX STI, and a sizable 52-hp increase compared to the current WRX. It would pair with a new, six-speed dual-clutch automated manual transmission to hit highway fuel-economy ratings of about 35 mpg.

The STI's 2.5-liter EJ turbo-four, a persistent workhorse since the 2004 Subaru WRX STI, will presumably be discontinued.

We saw a preview of the new Impreza's look in concept form at the Los Angeles auto show. If you can imagine a wider body with a meaner grille, flared-out fenders, carbon-fiber air ducts, rear diffuser, big honkin' rear wing, and more aggressive wheels and brakes, that's the familiar direction the next STI will take.

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A new global modular platform will underpin all new Subaru models starting with the 2017 Subaru Impreza, including the next WRX STI. Subaru is preparing the new architecture to support plug-in hybrid powertrains, so it's not impossible for the WRX STI to go hybrid. The unnamed source suggests testing is already underway.

On the other hand, Subaru has already laid out fairly extensive plans to reduce fuel-consumption without electric motors, including a transition to direct-injection engines across the lineup beginning in 2016. Cylinder deactivation is planned by 2020, along with leaner combustion cycles targeting better thermal efficiency. Historically the WRX STI has always had its roots in Subaru's World Rally cars, and hybrids have yet to enter that fray.

Hybridization makes sense for Subaru's more mainstream vehicles, but our bet is that if the Japanese automaker is developing electrified performance cars, they will reach production a few years further down the line than 2017.

We'll report back with more on the rumored Subaru WRX STI hybrid as we get it.