Launched in the States in mid-2011, the standard SLS GT is a 583-horsepower, all-aluminum, gull-wing coupe with performance that positions it near the top of the exotic segment. While the AMG team at Mercedes-Benz could have left it alone, their experience with the SLS AMG GT3 race car said there was room for improvement, so they devised the SLS Black Series. The transformation from SLS GT to SLS Black Series is extensive, with no fewer than 17 significant enhancements.
The engine mapping, crankshaft, connecting rods, valvetrain, intake, exhaust and cooling are all modified and the engine's redline bumps up from 7,200 to 8,000 rpm, which pushes output of the hand-built 6.3-liter V8 to 622 horsepower. The power steering receives a new ratio, a coilover AMG Adaptive Performance suspension is installed along with underbody braces, the track is widened, two-piece carbon-ceramic brakes replace iron rotors at each corner and a lightweight titanium exhaust is fitted beneath. The AMG Speedshift seven-speed dual-clutch gearbox is modified and an electronically controlled AMG rear differential lock ensures the power goes to the pavement. Last on the mechanical upgrades are new lightweight forged wheels (10x19 inches front and 12x20 inches rear) wrapped in special R-compound Michelin Pilot Sport Cup tires.
More visible are the cosmetic upgrades, which basically include new AMG aerodynamic bodywork forward of the A-pillar, carbon-fiber exterior mirrors, a fixed rear wing and other lightweight components. The interior of the cabin is also treated to unique Black Series Designo leather with Alcantara inserts. The short options list includes wheels with matte black paint, Bang & Olufsen BeoSound audio, COMAND multi-media interface and a fitted car cover to keep the dust at bay while at the track.
The SLS AMG Black Series weighs 3,417 pounds, which is 154 pounds lighter than its GT sibling, but its race car performance carries a $73,500 premium – in terms of engineering and tuning, many would consider it a bargain. To legally explore its performance, I spent the day with the automaker's flagship car at Willow Springs International Raceway in the Southern California Desert.
- The cockpit of the SLS Black Series is nearly identical to the GT in configuration, but the Alcantara removes some of its luxury polish. The synthetic suede is welcome, as its adds fingertip grip to the steering wheel and more friction to the seating surfaces. My six-foot, two-inch frame fit well, and legroom wasn't an issue, but the top of my racing helmet was brushing ever so slightly on the headliner with the gullwing door pulled snugly shut. The minor annoyance was forgotten when I pressed the red start/stop button on the center console and the V8 fired to life.
- Adding power, removing weight and raising redline are three easy ways to get my enthusiast pulse racing. The exhaust note on the standard SLS GT is impressive, but the titanium tubes on the Black Series sing a more aggressive song that easily permeated the side glass and drilled through my helmet – long live the wonderful naturally aspirated V8.
- The 40 additional horses improve acceleration slightly, but more important are the mapping changes to the gearbox. I ran the Black Series in S+ (Sport Plus) driving mode, which delivered crisp gear shifts and throttle blips coming into the corners. The upgraded programming is aggressive, but I never questioned its logic and found the coupe ran best when the computers were tasked with shifting.
- I'm used to running Big Willow in cars that need lots of throttle around Turn 2 and can go down the back straight flat-out. The 622-horsepower SLS had me at partial throttle around the constant radius turn and lifting down the back before entering dicey Turn 8. With a clean exit of Turn 9, I was able to hit a blistering 140 miles per hour down the front straight.
- Willow Springs is as old as your grandparents, with a track bed and surface that is really starting to show its age. While most of the pavement is smooth, some of the fastest corners are marked with dips and undulations that try their best to unsettle a chassis. Running the active dampers in their firmest setting was uncomfortable and unnerving, as some of the tires felt like they were losing contact with the road, so I backed the firmness off a stage to allow the wheels to follow the surface. Once I was running the proper setting, the grip from the wide and sticky Michelin tires (325/30ZR20 in the rear!) was extraordinary. Understeer has vanished, but oversteer remains just a stab of the throttle away.
- Tasked with less mass to stop and with tenacious carbon-ceramic friction surfaces, the brakes were a non-issue. Pedal feel was good, even though they didn't have race car firmness, and I rarely found the need to ask for ABS assistance even when the chassis was bounding over a bump on the surface. Some of the credit goes to those gummy tires, which refused to let go.
- A day at the racing circuit taught me that the SLS Black Series is a hardened track variant, which is best thought of as a tuned-down racecar rather than a gussied-up street vehicle. In terms of performance, nothing has been left untouched by the AMG engineers, and the car's performance at Willow Springs was nothing short of spectacular. This type of tuning is absolutely overkill for public roads, but I can't refrain from commending the brilliant engineers who were tasked with creating this uncompromising devil. It is one of my favorites.