The Mercedes-Benz R230 automobile was introduced in 2001. It was sold as the SL-Class convertible, replacing the R129. The SL500 was the top-selling version of the SL early in the R230 series. It used a 5.0 L V8 which produced 225 kW (302 hp) and 460 N·m (339 ft·lbf).
A 382 hp (285 kW) 5.5 L 4-valve V8 replaces the 5.0 L found in the SL500 for 2007. This model will retain the SL500 name in most markets, but will be sold as the SL550 in North America. It now produces 285 kW (382 hp) and 530 N·m (391 ft·lbf).
The SL600 is the highest-output version of the non-AMG SL models. It uses a twin-turbocharged V12 engine which produced 368 kW (493 hp) and 800 N·m (590 ft·lbf) from 2003 through 2006 and was uprated to 380 kW (510 hp) and 830 N·m (612 ft·lbf) for 2007.
The SL55 AMG version was released in 2002 with a supercharged 5.4 L (5439 cc) Mercedes-AMG V8. This car produced 493 hp (367 kW) at 6,100 rpm and could run to 100 km/h (62 mph) in 4.7 seconds.