The presentation of a new generation of Porsche 911 doesn't just represent the culmination of a new car's development. It also opens the door for a whole series of variants to follow. While we've seen the new 911 Carrera, Carrera S, Carrera 4 and Carrera 4S, and spy shots of the new GT3 undergoing testing, this very well may be the first look we've had at the upcoming new 911 Turbo. In this spy shot sent to us by a dedicated reader, we can see what appears to be the new 991-generation 911 Turbo being road-tested in the United States.

The shape of the tail-light (although partially camouflaged) and the positioning of the side-view mirror on the door itself (and not on the A-pillar like the previous model) tell us this is the new 991, while the presence of the split vertical vent in front of the rear wheel and the reshaped whale-tail rear wing (a hallmark of forced-induction Porsches) tell us we're most likely looking at a Turbo. Altogether the emergence of this solitary spy shot tells us that Stuttgart is already hard at work on the new 911 Turbo, which promises to bring untold levels of supercar performance in a versatile package.

Expect even higher output than the previous-generation 911 Turbo's 473 horsepower, driving all four wheels for a 0-60 time well into the three-second range. It may be several months before Porsche releases the new model, but expect more spy shots to emerge, so watch this space.