The E9's predecessor are 2000 C and 2000 CS models, which were produced from 1965-1969 as part of the BMW New Class range.
Models
2800 CS
The first of the E9 coupés, the 2800 CS, replaced the 2000 C and 2000 CS in 1968. The lead designer was Wilhelm Hofmeister. The wheelbase and length were increased to allow the engine bay to be long enough to accommodate the new straight-six engine code-named M30, and the front of the car was restyled to resemble the E3 sedan. The rear axle, however, remained the same as that used in the lesser "Neue Klasse" models and the rear brakes were initially drums - meaning that the 2800 saloon was a better performing car, as it was also lighter. The CS' advantages were thus strictly optical to begin with. The 2800 CS used the version of the engine used in the E3 sedans. The engine produced at 6000 rpm. Not only was the 2800 CS lighter than the preceding 2000 CS, it also had a smaller frontal aspect, further increasing the performance advantage. The curb weight of the 2800 CS is. At the 1969 Geneva Motor Show, BMW unveiled the "2800 Bertone Spicup" concept car. This model, which has a similar appearance to the 1967 Alfa Romeo Montreal, did not reach production.
3.0 CS/CSi
The 2800CS was replaced by the 3.0 CS and 3.0 CSi in 1971, which was bored out to give a displacement of. The 3.0 CS has a 9.0:1 compression ratio, twin carburetors and produces at 6000 rpm. The 3.0 CSi has a 9.5:1 compression ratio, Bosch D-Jetronicelectronic fuel injection, and produces at 5500 rpm. Transmission options were a 4-speed manual or a 3-speed automatic. In the United States, 1974 models have protruding 5 mile per hour bumpers.
3.0 CSL
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, unlike in other BMW designations, where it meant lang. 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 not 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 by increasing the engine bore by one quarter of a millimetre to. 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 by increasing the stroke to, rated at at 5600 rpm and at 4200 rpm of torque. 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". The CSL competed in Group 2 form in the European Touring Car Championship, with CSL drivers winning the Drivers title six times in the years 1973 and 1975 to 1979. The CSL also competed in Group 5 Special Production guise, winning three rounds of the 1976 World Championship for Makes. In FIA Group 4 spec, notably when driven by Hans-Joachim Stuck, they competed against racing versions of the Porsche 911 and Ford Capri with some success.
2.5 CS
The last version of the E9 to be introduced was the 2.5 CS in 1974. This was a response to the 1973 oil crisis, such that the buyer could choose the smaller, more economical engine. The engine, from the 2500 sedan, displaced and produced at 6000 rpm. Only 874 were made until the end of E9 production in 1975, and none were exported to the United States.
Motorsport
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 3.5 CSL was built for Group 5 racing and BMW won three races in the 1976 World Championship for Makes with this model.
In 2015, BMW introduced the 3.0 CSL Hommage concept car at the Concorso d'Eleganza Villa d'Este. The car is a tribute to the 3.0 CSL. It has an inline-six engine with an eBoost hybrid system in the rear of the car. As a homage to the original, the 3.0 CSL Hommage has a minimal interior to keep the weight as low as possible; carbon fibre and aluminium are used in the cockpit for the same reason. The Hommage has Laser-LED lights similar to those in the i8.
