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BMW 3.5 CSL

BMW 3.0 CSL
BMW 3.0 CSL
BMW 3.0 CSL
BMW 3.0 CSL

Total Production: 1,039
The 3.0 CSL race cars were the first cars to be developed under the new BMW subsidiary, established in 1972 – BMW Motorsport GmbH. They were also the first to sport the newly designated official colors of BMW Motorsport-red, blue and purple.

Based on the 3.0 CS coupe production car, the CSL ('L' is for lightweight, referring to the aluminum doors and hood) began an assault on European touring car racing that would make it one of the most successful production racers of all time. In fact, CSL's continued to win races into the late 1970's, even though series production ended in 1975 to make way for its successor, the 6 series.

Throughout its span of development, the BMW six-cylinder engine, a 3.0 liter unit in the production car, grew from 3.2 to 3.5 liters, increasing in horsepower from 340 to 430, thanks to the development of a four-valve cylinder head.

The 3.0 CSL won six European Touring Car Championships between 1973 and 1979, as well as national championships in several other countries.

This 3.0 CSL was one of a team of three cars campaigned by BMW of North America in 1975 & 1976, enjoying considerable success, winning IMSA races at Sebring, Laguna Seca, Riverside, Daytona, Lime Rock and Talladega. Several drivers were involved in the CSL's American success including Hans Stuck, Sam Posey, Brian Redman, Ronnie Peterson, Dieter Quester, Benny Parsons, Peter Gregg and David Hobbs.

Source - BMW Motorsports
The BMW 3.0 CSL was a brilliant car introduced at a time when the Touring Car racing class had gained proper popularity and there was a strong demand for a competitive vehicle. The class had increased in popularity with the four-door saloons such as the Ford Cortina and the Alfa Romeo Giulia. Rule changes were later added which required the cars to have only two doors, making the prior cars obsolete. Alfa Romeo introduced their GTA and BMW their 2002. Other requirements for this class required a minimum of 1000 units to be produced to satisfy homologation. Alfa Romeo's cars proved to be very competitive, and were soon dominating the European Touring Car Championship (ETCC).

The European Touring Car Championship began in 1963, created by Willy Stenger and organized by the FIA as a international Touring Car Racing Series. There have been two versions of this series, the first lasting from 1963 through 1988 and the second from 2000 through 2004. When first created, the touring cars allowed a plethora of touring cars, ranging from dimension size to engine displacement size. Classes segregated the 'standard' cars from the 'modified' cars, the 'touring' cars from the 'Grand touring' cars, and so-forth.

A variety of cars competed in this series, including Mini Coopers, Mercedes Benz 300SE, Jaguar Mark II, Fiat 600, and even the Chevrolet Camaro. Porsche tried to get their 911 homologated, but it was rejected due to having too small of a rear seat. Part of their problem may have been that they had the car homologated for the GT category; other cars such as the Alfa Romeo Giulia GTA were allowed in the Touring car category, but their rear accommodations were almost equally as cramped. Rules were pretty relaxed during the early years; all that was needed was seating for four and homologation requirements were satisfied. BMW cars raced in this series beginning in 1964.

The BMW Company had been known for its large, V8 powered luxury cars, but the turn of the 1960s saw them migrate to a new market of vehicles, the sporty, four- and six-cylinder cars. The cars still came with a relatively heft price tag, but the price was well worth the package. The cars were well suited for the Touring category; their engines were reliable, durable, and powerful. The tuning company Alpina even joined BMW factory works efforts in the ETCC.

The change from the large, stately, V8 powered cars to the four- and six-cylinder cars proved to be a wise decision. The company was able to regain their financial stability.

When Ford of Europe joined the ETCC in 1970, the rivalry was almost instantaneous. Their Capri Coupes were powered by V6 engines and the vehicle's construction was lightweight and rigid. BMW and their modified 2800 CS were outclassed by the Capri Coupes; the BMW engine and their three Weber carburetors produced 300 horsepower. The Achilles heel to the BMW was its weight, and the factory began work on creating a new vehicle to combat the Fords. Alpina began work on improving the BMW and the engine. The Weber carburetors were removed and replaced with a Kugelfischer fuel injection system which brought horsepower over 330. Weight was reduced bringing it in the territory of the Fords. The trim and sound-proofing materials were removed. The doors and trunk lid were created from aluminum and the monocoque was formed from thinner-gauge steel. A total of 550 lbs had been shaved. This is where Alpina's abilities ended; BMW stepped in to help them produce the necessary numbers required to satisfy homologation. BMW recruited Jochen Neerpasch and Martin Braqungart to help them establish the BMW Motorsport department. Neerpasch and Braqungart had been working for Ford Racing, so this move only heightened the rivalry between the two companies.

When BMW introduced their 3.0 CSL, Neerpasch and Braqungart had still been with Ford. The Capri managed to outpace the BMW, so that is when BMW decided to recruit Neerpasch and Braqungart into their fold.

The BMW 3.0 was powered by a 3.0-liter six-cylinder engine that produced 180 horsepower. Displacement size was increased to 3.2-liters beginning in 1973, though it still retained the '3.0 CSL' name. Neerpasch and Braqungart improved the vehicle's downforce by adding a deep front air dam, increased the fenders, and added a trunk-lip spoiler. A very large rear wing earned it the nickname, the 'Batmobile.' The cars did not leave the factory with the wing since they were illegal for road use. The company sold the vehicles with these accessories enclosed in the trunk of the car. They were not installed on the vehicle as they left the factory but left up to the customer to assemble. In this fashion, the company was able to side-step the homologation process.

In 1973, the 3.2-liter engine was increased further to 3.5-liters; the four-speed gearbox was replaced in favor of a five-speed Getrag unit. The weight of the vehicle was further reduced by 150 kg.

The BMW 3.0 CSL was entered mostly by the Factory during the 1973 season. Alpina and Schnitzer also fielded cars. The Ford's still provided fierce competition, but at the conclusion of the season, BMW driver Tone Hezemans had captured the Drivers' Title and BMW had earned the Manufacturers' Title.

At the conclusion of the 1973 season, BMW worked hard on keeping their vehicles competitive. Ford did the same. Both companies developed twin-cam, four-valve per cylinder heads, which greatly increased the engine's horsepower to over 400. Ford worked on improving their aerodynamics and downforce, to similar BMW 'Batmobile' standards.

The Oil Crisis limited the number of entrants in 1974. Ford and BMW sat out the first round, both waiting to unveil their vehicles at the second event. At Nurburging, Ford easily took the checkered flag, as all ten BMW entrants failed to finish due to reliability issues. After this dismal performance, BMW left the series, leaving Ford to claim the overall victory. Ford driver, Hans Heyer was crowned with the Drivers' Title at the conclusion of the season. This would be Ford's final year in the series, leaving their cars in the capable hands of privateers. Alpina and Schnitzer continued to race the 3.0 CLSs, and Alpina was rewarded with top honors for the 1975 season.

1975 had seen very few participants; rule changes in 1976 were aimed at increasing participation and reduce costs. The four-valve head engines and body kits were banned, making the BMW and Fords obsolete. In 3.2-liter form and fitted with the four-speed gearbox, the BMW's continued to provide strong competition and often finished ahead of its competitors.
By Daniel Vaughan | Jul 2007

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