The 2008 Mercedes-Benz CLK63 AMG Black Series makes its debut as an ultra-high-performance addition to this premium sporty car's roster. CLKs are available as coupes or convertibles. The coupes have hardtop styling with no middle roof posts. Convertibles have a power fabric top, heated glass rear window, and roll bars designed to pop up if sensors detect an impending rollover. The CLK's model lineup consists of the following: the CLK350 with a 268-horsepower 3.5-liter V6 engine; the CLK550 with a 382-horsepower 5.5-liter V8; CLK63 AMG with a 475-horsepower 6.2-liter V8; and new CLK63 AMG Black Series with a 500-horsepower 6.2 V8. All have a 7-speed automatic transmission. CLK350 and CLK550 come in both body styles. The CLK63 AMG is a convertible, and the Black Series is a coupe. Available safety features include ABS, traction control, curtain side airbags (coupes), and front and rear side airbags. Options include a navigation system and keyless entry and starting. Black Series models have specific trim and suspension tuning. This evaluation is based on preview test drives.