The Mercedes SLS AMG Black Series was spied recently while doing some hot laps around the Nurburgring racetrack in Germany. Unfortunately, there are no official details of the SLS AMG Black Series at the moment. Rumors say it's going to be powered by a 6.3-liter V8 engine that will output more than 600 hp. So far, we know that the SLS AMG Black Series will be produced in limited numbers, but its launch date and price are still a mystery.