The Porsche 911 GT3 RS is now in Sweden for cold-weather testing. Our spies have 35 pictures of it, and the shots provide a comprehensive look at the upcoming performance model's current state of development.

The development team is putting a clear emphasis on the way the RS cuts through the air. The front fascia is similar to the one on the standard GT3. There's tape over each corner, so the company has something to hide. In addition, the vents in the bonnet are significantly larger than on the regular model.

Gallery: Porsche 911 GT3 RS Winter Spy Shots

Things get even more complicated along the side, and Porsche tries hard to hide the pieces there. There appear to be vents along the top and a vertical flying buttress. Our spies note that the RS has doors with revised sculpting along the lower portion. Look closely at the rear quarter panels, and you can notice a large panel that is hiding inlets.

At the back, there's a swan-neck wing, and the engineers put material on the uprights to conceal their actual design. Videos show that it's capable of active adjustments to switch between high- and low-downforce configurations. Strakes guide air into the rear deck, and there's tape on the section in the centre.

Also, there's black tape on the bumper to hide portions of it. A diffuser attaches to the bottom. The exhausts seem to be missing the polished finishers that we see in earlier spy shots. 

The GT3 RS reportedly still uses a 4.0-litre flat-six engine. The output is allegedly a bit more than the previous generation's 520 bhp (383 kilowatts). The powerplant's redline might be as high as 9,500 rpm. The vehicle's sound in videos suggests it uses a dual-clutch gearbox.

Look for the GT3 RS to debut later this year, and deliveries should start in 2022, too.