SPY PICS: 2022 Porsche 911 GT3 RS hits the track

Porsche is putting the finishing touches on the most extreme Porsche 911 GT3 RS ever created, with a late-stage development mule spotted testing at the Nurburgring.

Expected to arrive in 2022 along with a facelifted 992.2-series version of the current Porsche 911, the barely disguised test mules reveal a big aero update over the regular, and already extreme, Porsche 911 GT3.

Dominating the design of the 2022 Porsche 911 GT3 RS is a super-sized version of the standard GT3's wing that once again employs saw-neck mounts.

Not only is that wing huge, it's believed to be technically advanced too, employing active elements that vary downforce and even include an F1-style DRS system for higher top speeds on the straights.

Other significant changes include a wider front and rear track for higher cornering grip that looks like it requires Porsche to fit wider front and rear fenders.

New fender extractors, front air curtains, a new splitter, subtle side skirts and a reprofiled front bonnet are further evidence of what's likely to be hundreds of detail changes.

At the rear, an ugly squared-off bumper signals the extent engineers and stylists are willing to go to in order to gain an advantage on a hot lap.

Under the rear boot lid, expect only modest power gains over the naturally-aspirated 375kW/470Nm 4.0-litre flat-six in the 2021 Porsche 911 GT3, but a weight saving of anything between 50-100kg should see a couple of tenths knocked off the regular GT3's 3.4sec 0-100km/h sprint.

What will be missing will be a six-speed manual, with all RS models set to come with the seven-speed dual-clutch automatic transmission as standard.

When it eventually lands in 2022, expect the faster, more hard-core take on the 911 GT3 to cost around $420,000 – around $50,000 more than a PDK-equipped 911 GT3.