The GT2 RS could boast 650 horsepower..

Porsche will introduce at least two new variants of the 911 this year.

The first one is an updated version of the 911 GT3. Set to debut in March at the Geneva Auto Show, the model will get a 4.0-liter flat-six engine tuned to produce about 500 horsepower. The same six-cylinder powers the GT3 RS, and the 911 R that's selling for insane amounts of money on the used car market.

Enthusiasts will be able to order the 991-series GT3 with a six-speed manual transmission for the first time. A quick-shifting, seven-speed dual-clutch automatic transmission with shift paddles will also be available.

British magazine Autocar reports the Stuttgart-based automaker is preparing to bring back the 911 GT2 RS nameplate. Designed for the track, the GT2 RS will get a twin-turbocharged, 3.8-liter flat-six engine pulled out of the 911 Turbo S parts bin and cranked up to 650 horsepower. 700 horsepower wasn't attainable without using a water-injection system, sources told the magazine.

The 911 GT2 RS will be rear-wheel drive only. At this point, it's too early to tell whether it will be offered with a manual transmission, a dual-clutch automatic, or both.

More details about Porsche's next 911 variants will emerge in the coming months. If the rumors are accurate and the GT3 debuts in Geneva, we'll be on-location to bring you live images of it as soon as it breaks cover.

Note: Porsche 911 GTS pictured.