Sophisticated, classy, refined, cosmopolitan – all words that could all be used to describe the new 630 CS coupe, introduced by BMW in 1976. The new coupe shared the sporty handling platform of the BMW 5-Series sedan, but stepped up the luxury and comfort features to compete against the Jaguar XJ-S and the Mercedes-Benz 450 SL/SLC. While the design was inspired by the 1972 BMW Turbo show car, the 630 CS did not have the aggressive, cutting-edge styling of the show car, but was designed to look good for the long run – truly a timeless design.
The BMW 630 CSi
The planning for the successor to the aging 3.0 CSi began in the early 1970s, amid tumultuous times at BMW. The company’s chairman, styling director, and production chief all had retired and their sales boss had resigned, leaving very little, if any, continuum of thought or planning for the next coupe. A conflict developed among the new management team, with one faction hoping to keep the sporty image of the coupe’s heritage, while another group wanted to make it more stately and dignified. Fortunately for BMW fans everywhere, the sporty image group prevailed. Both groups agreed, however, that the coupe would be moved upscale to challenge the Jaguar and Mercedes-Benz sports coupes.
To help hold down development costs, the new coupe would share the 5 Series sedan platform. It would be bigger and heavier than its predecessor, primarily to meet U.S. safety regulations. Designed by former Mercedes-Benz designer Paul Bracq, who took inspiration from the 1972 BMW Turbo show car, the new 630 CSi was considered to be “handsome” by the media following the introduction in February of 1976. BMW aficionados, on the other hand, were more reserved, many considering the 630 CSi to be an overweight boulevardier inferior to the company’s sporty sedans. Sales were initially modest, with 4,933 coupes finding new homes in 1976. But the 630 CSi was designed for the long haul; better times were ahead.
BMW’s timeless design and continued improvement
In early 1977, BMW increased the displacement of the inline six-cylinder engine to 3.3 liters and renamed the coupe the 633 CSi. The single overhead cam powerplant also raised the compression ratio up to 8.4:1 and had the latest Bosch L-Jetronic fuel injection system, resulting in 177 net horsepower @ 5500 rpm. According to the September 1978 issue of Road & Track magazine, the U.S. version of the 633 CSi had a 0 to 60 mph time of 8.4 seconds, 1.3 seconds quicker than the 630 CSi, and could cover the quarter mile in 16.8 seconds with a terminal speed of 84.5 mph. Top speed was around 131 mph.
The body was of all-steel monocoque construction and featured a chassis with independent front and rear suspensions. The transmission was either a four-speed manual or a three-speed automatic, which transferred the drive to the rear wheels through a limited-slip differential. In the cockpit, BMW pulled out all of the stops to get a leg up on the competition. Standard equipment in the U.S. included an electric sunroof, air conditioning, power windows, power-assisted steering, an AM-FM stereo-cassette player with an eight-speaker sound system, heated power seats, and something you don’t see every day – a beverage chiller between the two rear seats.
The Hofmeister Kink
The 6-Series had many of the traditional BMW styling cues, to let everyone know it was a BMW even if the logo could not be seen. One of the cues was the kidney-shaped, twin grilles. Another was the ‘Hofmeister Kink’. The ‘Hofmeister Kink’ is an automotive design detail by which a BMW tells your subconscious mind, “Hey, I’m a BMW.” The ‘Kink’ appears in the rear side window line after it turns down to approach the top of the rear fender, but shortly before meeting the fender, it takes a sharp turn, or ‘kink’, toward the front of the car, forming a small triangular wedge in the C-pillar between the rear side window and the rear window. In some models, a BMW logo is placed in the triangular wedge.
The ‘Kink’, named after its creator Wilhelm Hofmeister, BMW’s chief designer from 1955 to 1970, has been used on all BMWs since the Neue Klasse Bimmers of the early 1960s. The design cue has been so identified with BMWs, that now other car marques are adopting it to “borrow” some of the BMW’s cachet. The automotive design world considers the ‘Hofmeister Kink’ to be one of the ten best car design elements, along with such design icons as the Porsche 911 silhouette, the wedge designs of the ‘70s, and tailfins and Dagmar bumpers of the ‘50s. BMW claims that the ‘Kink’ “subtly highlights” the fact that the cars are rear wheel drive.
BMW 6-Series heritage
Although BMW made their name in the marketplace in the 1960s primarily with sedans, beginning in 1965 they offered the 2000 C and the 2000 CS, upscale two-door coupes powered by two-liter, four-cylinder engines. The new coupes were modest sellers and were replaced in 1968 with the larger, more powerful 2800 CS coupe. The 2800 CS had an all-new body accommodating a 2.8 liter, inline six-cylinder powerplant, which was good for 170 horsepower. Despite the increase in horsepower, the BMW coupes acquired a reputation as being spirited and comfortable drivers, but they didn’t make a big impression in racing circles.
BMW changed that impression following the introduction of the 3.0 CS and 3.0 CSi in 1971. The 3.0 coupes shared the body style of the 2800 CS, but boosted the power output with a new three-liter six-cylinder engine which, with Bosch D-Jetronic fuel-injection, produced 200 horsepower. The next step for the boys from Bavaria was to conquer the racing world. They created a lightweight 3.0 CSL with thinner steel, aluminum doors, hood, and trunk lid, and Plexiglas windows, which was homologated for racing in the European Touring Car Championship (ETCC). With an aerodynamic package including a large front air dam, short fins running along the front fenders, a roof spoiler and a tall rear wing, the car called the “Batmobile” won the ETCC in 1973 and from 1975 to 1979. The BMW coupe had marked its territory and it now included the race tracks of the world.
“A great GT car”
Road & Track’s comment about the 633 CSi is an apt summary of the history of the BMW 6-Series: “All in all, the BMW 633 CSi is a perfect example of engineering improvements and comfort refinements that make a great GT car even more pleasurable.” Despite the modest initial reception of the 6-Series in 1976, its timeless design and continued improvements eventually won over the hearts of the BMW faithful. Sales of the 6-Series increased throughout the seventies and into the eighties, reaching a peak in 1985 with 9,626 Coupes. Sales declined after 1985, but by the end of production on April 6, 1989, 86,216 6-Series BMWs had been sold. The 6-Series had persevered to become a great GT car.
Ate Up With Motor – https://ateupwithmotor.com/model-histories/bmw-e24-6series/
Classic and Vintage BMW – http://classicandvintagebmw.tumblr.com/78randt633csitest
Wikipedia – https://en.wikipedia.org/wiki/BMW_6_Series_(E24)
E24 BMW 6-Series – http://e-24.ru/eng/theory/evolution/1976/
New Media Campaigns – https://www.newmediacampaigns.com/page/the-hofmeister-kink-a-lasting-bmw-design-detail