a more track-oriented "S" setting. A 6-speed Getrag 420G manual transmission was introduced in 1994. M-System wheels The M5 came with an unusual wheel design. From 1988 to 1992 the M5 featured the three-piece Style 20 "M-System" wheels, which consisted of magnesium, unidirectional bolted-on wheel covers and an aluminum assembly with concentric fins that bolt on to the front of the black, 5-spoke forged aluminum wheel. According to BMW, the cover increased outside airflow to the brake assembly by 25 percent to improve cooling. In 1992 BMW changed the design to the "M-System II" (nicknamed "throwing stars") which improved brake cooling from the combination of the larger openings and fins placed in the driving direction. In May 1994, the M5 switched to 18-inch Style 37 "M Parallel" wheels that did away with the finned cover entirely. Special editions There were four special editions of the E34 M5. The Cecotto, Winkelhock and 20 Jahre editions which were offered as LHD Euro specification models while the RHD UK Limited edition was only sold in the United Kingdom. In 1991, BMW asked two race drivers to design their "ideal" version of the E34 M5. The Cecotto Edition M5, named after Johnny Cecotto, featured severy luxury items fitted, including Nappa leather for the steering wheel and heated seats. A total of 22 Cecotto E34 M5s were produced with options of having either Lagoon Green metallic (code number 266) and Mauritius Blue metallic paint (code number 287) and Light Parchment or Light Silvergrey upholstery for the interior. The other M5 special edition dedicated to a race driver was the Winkelhock Edition, named after touring car driver Joachim Winkelhock. The resulting car was a lightweight M5 stripped of some amenities. The Winkelhock Edition features a smaller battery, the reduced US-spec 81-litre fuel tank, reduced sound deadening, and deletion of non-essential items such as rear headrests, vanity mirrors, rear window switches and foglights. The Recaro front seat design, suede-covered 385mm M-Technic II steering wheel, shift knob and parking brake handle, and red seatbelts were similar to those on the BMW E30 M3 Sport Evolution. A total of 51 Winkelhock E34 M5s were produced with the options of having Jet Black (code number 668) with contrasting lower body panels in Sterling Silver metallic paint (code number 244). The 20 Jahre Motorsport Edition was built to celebrate BMW Motorsport's 20th anniversary in 1992. Twenty cars were produced, all Euro-spec