The BMW New Six CS (internal name BMW E9) was a two-door coupé built for BMW by Karmann from 1968 to 1975. It was developed from the New Class-based BMW 2000 CS coupé, which was enlarged to hold the BMW M30 straight-6 engine used in the E3 sedan.
The E9 platform, especially the 3.0 CSL homologation special, was very successful in racing, especially in European Touring Car Championship and the Deutsche Rennsport Meisterschaft. This helped to establish BMW's status as a sporty driver's car.
Introduced in May 1972, the 3.0 CSL was a homologation special built to make the car eligible for racing in the European Touring Car Championship. 1,265 were built.
The "L" in the designation meant leicht (light), unlike in other BMW designations, where it meant lang (long). The lightness was achieved by using thinner steel to build the unit body, deleting the trim and soundproofing, using aluminium alloy doors, bonnet, and boot lid, and using Perspex side windows. The five hundred 3.0 CSLs exported to the United Kingdom were not quite as light as the others, as the importer had insisted on retaining the soundproofing, electric windows, and stock E9 bumpers on these cars. The CSL was never sold in the United States.
Initially using the same engine as the 3.0 CS, the 3.0 CSL was given a very small increase in displacement to 3,003 cc (183.3 cu in) by increasing the engine bore by one quarter of a millimetre. This was done in August 1972 to allow the CSL to be raced in the "over three litre" racing category, allowing for some increase in displacement in the racing cars. In 1973, the engine in the 3.0 CSL was given another, more substantial increase in displacement to 3,153 cc (192.4 cu in) by increasing the stroke to 84 mm (3.3 in). This final version of the 3.0 CSL was homologated in July 1973 along with an aerodynamic package including a large air dam, short fins running along the front fenders, a spoiler above and behind the trailing edge of the roof, and a tall rear wing. The rear wings were not installed at the factory, but were left in the boot for installation after purchase. This was done because the wings were illegal for use on German roads. The full aero package earned the racing CSLs the nickname "Batmobile".
Chris Amon, Winner of 6 Hours Race 1973 at Nürburgring with BMW 3.0 CSL
In 1973, Toine Hezemans won the European Touring Car Championship in a 3.0 CSL and co-drove a 3.0 CSL with Dieter Quester to a class victory at Le Mans. Hezemans and Quester had driven to second place at the 1973 German Touring Car Grand Prix at Nürburgring, being beaten only by Chris Amon and Hans-Joachim Stuck in another 3.0 CSL. 3.0 CSLs would win the European Touring Car Championship again in every year from 1975 to 1979.
The 3.0 CSL was raced in the IMSA GT Championship in 1975, with Sam Posey, Brian Redman, and Ronnie Peterson winning races during the season.
The first two BMW Art Cars were 3.0 CSLs; the first was painted by Alexander Calder and the second by Frank Stella.
The 3.5 CSL was built for Group 5 racing and BMW won three races in the 1976 World Championship for Makes with this model.