Porsche->ke1 was quite the busy bee in 2014. The brand-new Macan->ke4210 crossover was launched in the second quarter of the year, while a facelifted Cayenne->ke4210 surfaced a few months later. Additionally, Porsche is testing several updated sports cars->ke506, including the Boxster/Cayman duo, the 911 convertible and the upcoming GT3 RS. More recently, Porsche also brought the Cayenne GTS to the Nurburgring->ke999, signaling that its facelifted SUV->ke145 lineup will soon include another member.

While the Germans unveiled the revamped Cayenne in July 2014, there was no word on the mid-level GTS and the range-topping Turbo S. The latter is still a well-guarded secret as of August 2014 -- though we know we'll get one at some point -- but it seems development of the former is well underway with a prototype spotted trotting around the Nurburgring.

Details are slim as of this writing, but the video reveals Porsche has slapped a new set of bumpers on the GTS, along with the revised headlamps and taillights already seen on the 2015 Cayenne. A new exhaust system is present on the prototype as well, but the big news lies under the SUV's hood. By the sound of it, the GTS is no longer motivated by the naturally aspirated, 4.8-liter V-8 that we all know and love. The Cayenne S has already ditched the large unit in favor of a twin-turbo, 3.6-liter V-6, and it appears the GTS did the same thing.

The unit delivers 420 horsepower and 406 pound-feet of torque in the Cayenne S, so it's only natural to expect some extra oomph from the GTS-spec V-6. As usual, the SUV will include a tweaked suspension and interior upgrades.

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