Porsche’s latest Type 991 variant of the 911, the high-performance 911 GT3, is set to debut at the Geneva Motor Show in March. Earlier this week, we brought you camo-free spy shots of the car in winter testing, and even speculated that a PDK dual-clutch transmission would replace the formerly standard manual gearbox.

Over on the Rennlist forum, a member has posted pictures and a bit of information about the new 911 GT3, based on a conversation with the test driver and Porsche engineers. Apparently the new GT3 will get a “completely different” version of the PDK gearbox, and it’s believed that this will be the only available transmission.

Though the flat-six engine remains at 3.8-liters, word is that the block is all new and will be shared with the new Porsche 911 GT3 Cup car. Redline is an impressive 9,000 rpm, and output is “north of 450 horsepower,” though the Porsche engineers wouldn’t provide additional details or specifics.

The GT3 will reportedly get the same wider body used on the Carrera 4, and it appears that the car will ride on center-lock 20-inch wheels, shod with 305mm tires in the back and 245mm tires up front. There’s a new brake system employed, using an oversized (presumably six-piston) front caliper with drilled rotors.

Inside, the model spotted wore new folding Recaro seats, and came equipped with the rear cage fitted to Clubsport models. As for performance, Nürburgring lap times are said to be in the 7:30 range, which could potentially indicate that the car is faster than the Type 997 Porsche 911 GT3 RS.

We'll bring you all the details on the new Porsche 911 GT3 as part of our 2013 Geneva Motor Show coverage. To see the images of the car caught in testing, head on over to the Rennlist forum page.