A new version was introduced in 2006, called the Mercedes-Benz SLR McLaren 722 Edition. The “722” refers to the victory by Stirling Moss and his co-driver Denis Jenkinson in a Mercedes-Benz 300 SLR with the starting number 722 (indicating a start time of 7:22 a.m.) at the Mille Miglia in 1955.
The “722 Edition” includes an engine rated 650 PS (480 kW; 640 hp) at 6,500 rpm and 820 N·m (600 lb·ft) at 4,000 rpm. 19-inch light-alloy wheels were used to reduce unsprung weight, while modifications were also made to the suspension, with a stiffer damper setup and 10 mm (0.39 in) lower ride height introduced for improved handling. Larger 390 mm (15 in) diameter front brakes and a revised front air dam and rear diffuser were fitted.
Exterior changes, other than the larger 19-inch (480 mm) black light-alloy wheels, include red “722” badging, harking back to the original 722 racer, and slightly different tail lights and headlamps.
The SLR 722 can accelerate from 0 to 100 km/h (62 mph) in 3.6 seconds, 200 km/h (124 mph) in 10.2 seconds and 300 km/h (186 mph) in 27.6 seconds, and can reach a top speed of 337 km/h (209 mph) faster than the standard Mercedes-Benz SLR McLaren.
A roadster version of the SLR went on sale in September 2007. It uses the same supercharged V8 AMG power plant as its coupé siblings, developing 626 PS (460 kW; 617 hp), to propel it to a top speed of 334 km/h (208 mph) and a 0 to 100 km/h (62 mph) acceleration time of 3.1 seconds.
However, as a convertible the roadster was burdened with extra weight, which affected performance and handling. The Roadster’s roof is made from a “newly developed material” and does not take the form of a folding metal arrangement, as is common on many modern cars. Following a manual unlatching, it takes ten seconds to fold away electrically. According to an official Mercedes document, the cabin of the roadster is capable of allowing conversation between driver and passenger up to a speed of 200 km/h (120 mph) with the roof retracted. This roadster is aimed to compete against other sports cars such as the Pagani Zonda F Roadster.
A limited edition (150 units) of the 722 coupé. It can reach 100 km/h (62 mph) from standstill in 3.6 seconds and has top speed of 334 km/h (208 mph). The model went on sale in January 2009.