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Thirty years ago, BMW’s “large class” spawned a successor that
was to become a byword for luxury, elegance and innovation: the BMW 7 Series.
Drawing on technology based on the large 6 Series Coupé launched in 1976 and
styling that bore the signature of BMW’s chief designer Paul Bracq, BMW
succeeded in creating a car that was larger than its predecessor yet managed to
retain the hallmark dynamics associated with the brand.
The ingeniously tailored, understated bodywork borrowed its main styling cues
from the BMW 6 Series Coupés. The gently sloping bonnet and boot, short
overhangs and low beltline granted occupants excellent visibility, helped by a
glass area that was 11 percent larger than its predecessor’s. The BMW engineers
had also carried out modifications in the chassis technology and on the safety
front. New features included front-wheel suspension with double-joint spring
struts, a reduced steering offset and anti-dive, as well as a closed-shell rear
axle subframe that offered far greater rigidity and improved corrosion
protection. Like the other cars in the BMW portfolio, the 7 Series models also
came with a centre rollover bar. In conjunction with all-round roof
reinforcements and strong loadbearing pillars, this created a very large
integrated safety structure to secure the survival space of occupants even in
extreme impacts.
With the newly launched BMW 7 Series joining the 3, 5 and 6 Series ranges,
BMW now had a complete model family whose various members were instantly
recognisable as being “related” thanks to their similar, yet distinctive,
designs. “Visual and technical unity is now assured across all the model
series,” is how Hans-Erdmann Schönbeck, the sales director of the time, put it.
“The BMW models are now indisputably a ‘family’ once more with many shared
features.”
Initially customers could choose from three models: the 2.8-litre, 3.0-litre
and 3.2-litre with 170, 184 and 197 hp respectively. Base prices were DM 29,300
for the BMW 728 and DM 33,600 for the 730, while an extra DM 5,000 would buy the
top-of-the range 733i.
Even the BMW 728 boasted standard specifications that included
speed-sensitive power steering, a diagonal-split dual-circuit brake system,
inner-vented front brake discs together with a newly developed hydraulic brake
servo, a laminated front windscreen, adjustable steering column and seat height,
and an electrically adjustable exterior mirror. The BMW 730 ushered in the
Check/Control system, an electronic monitoring unit that checked the level of
the engine oil, brake fluid, coolant and windscreen washer fluid, as well as the
functioning of the brake lights and rear lights, and the thickness of the brake
linings. Beyond this, the top-ranging 733i featured not only a Bosch L-Jetronic
injection system, but also boasted a contactless transistorised ignition,
central locking, heat-insulating glass and a leather steering wheel.
In addition, customers could order from a long list of optional extras to
equip their BMW 7 Series to personal taste. These included automatic
transmission, a steel slide/tilt roof, headlamp washer and wiper, air
conditioning, electric window lifts, self-levelling rear suspension, metallic
paintwork, leather upholstery and separate electrically adjustable seats in the
rear. The range of special equipment was augmented by “sporty extras” such as a
limited slip differential, alloy wheels and a leather sports steering wheel.
The BMW 7 Series enjoyed an extremely successful market launch. At the Annual
General Meeting of 7 July 1977, BMW’s Chairman of the Board Eberhard von
Kuenheim announced: “The volume of orders is so unexpectedly high that the
Dingolfing plant can barely keep up with production.” Company turnover had risen
by 32 percent the year before and BMW was turning out 24 percent more cars and
10 percent more motorcycles. The upward trend continued in the first half of
1977, which meant that the workforce again had to put in several extra shifts to
keep up with the surging demand. To ensure that international customers could
also buy the flagship car from the start, right-hand-drive versions were offered
at an early stage. In July the first CKD kits were shipped out to the BMW plant
in South Africa. December also saw the production start-up of a special version
of the 733i targeted at the highly important North American market. In 1977
production figures for the BMW 7 Series ran to almost 20,000, a figure that
would rise to 35,745 cars in the first full year of production and still exceed
35,000 units in the subsequent two years. The bottom line was that the BMW 7
Series was more successful than any previous BMW model series in its class.
The early years of the 7 Series already saw the regular addition of further
optional extras. In 1978 BMW began offering its Anti-lock Braking System (ABS).
To make driving BMW’s top-of-the-line model even safer and more comfortable, it
also launched features such as an anti-theft warning system, driver's vanity
mirror and heated door locks, heated seats, onboard computer, cruise control,
sunblinds for the rear windscreen and automatic air conditioning. For business
people who spent a lot of time on the road, telephone preparation was also
available.
From late August 1979 the large BMW six-cylinders were offered exclusively
with fuel-efficient injection engines. The BMW 728i with an output of 184 hp
replaced the 728, and the previous 733i was renamed the 732i. While displacement
and output remained unchanged, enhancements included the newly developed digital
engine electronics, incorporated for the first time in a BMW production model.
This system used a microcomputer to calculate the precise ignition angle and
quantity of fuel to be injected in any operating conditions. A newcomer to the
range was the BMW 735i with the 3.5-litre 218 hp engine familiar from the
635CSi.
Ready for delivery in early summer of 1980, the new top-of-the-range model of
the first-generation 7 Series – the BMW 745i featuring a 252 hp six-cylinder
engine with exhaust turbocharger and 3-speed automatic transmission as standard
– was handed over to the first customer. The model designation derived from the
conventional formula applied to turbo models in motor sport at the time: engine
size multiplied by a factor of 1.4 gave you the displacement class in which the
turbo cars were deployed on the race track. For the BMW 7 Series with its 3210
cc displacement, the calculation produced the figure 4494. The 3.2-litre
turbocharged six-cylinder delivered driving performance that was hard to match
in the saloon sector.
Outside the official product range, and therefore unnoticed by the public,
BMW produced a 725i model powered by the 150 hp engine taken from the BMW 525i
and designed for use by public authorities, whose cars were frequently
restricted to an engine size of 2.5 litres. To ensure that these potential
customers still had the option of choosing a 7 Series model, BMW decided to
install the tried and tested engine from the 5 Series. By the time production
was phased out in April 1986, a total of 921 examples of this special model had
been built. Similarly targeted primarily at public bodies, BMW introduced a
reinforced version of the 7 Series as a security vehicle in 1981.
In September 1982 a number of technical and visual changes began to be phased
in as part of a model revision. On the outside the hallmark BMW kidney grille
was slightly flatter, the air intake in the radiator grille was smaller and the
panel under the bumper had been modified. The top-of-the-range 745i now had a
3.4-litre engine under its bonnet, though output remained unchanged, as well as
a 4-speed automatic transmission. The BMW 735i and 745i also came with the
option of Executive leather upholstery at an extra cost of DM 3,390. Model year
1984 brought the option of a 4-speed automatic transmission with
electric-hydraulic control and three shift modes. In the autumn, the BMW 7
Series range was augmented by two more luxury models: the BMW 735i Highline and
the 745i Highline with high-luxury specifications.
By the time this series was discontinued in June 1986, production figures had
hit 285,029. The most popular model was the 728i, which sold 70,360 times,
followed by the 735i with sales of 60,818. A total of 16,848 BMW 7 Series alone
went to South Africa as CKD kits. It was here, too, that the most powerful of
the BMW 7 Series found a market. Early 1984, practically unobserved by the
European public, saw the launch of a special version of the 745i powered by the
four-valve-per-cylinder, naturally aspirated M88/3 engine from the BMW M1.
Thanks to its L-Jetronic fuel injection system, output was boosted to 290 hp,
while power was managed by either a 5-speed sports gearbox or a 4-speed
automatic transmission with electronic-hydraulic control and three shift modes.
BBS Mahle provided the alloy wheels and Pirelli supplied the proven P7 tyres in
205/55 or 225/50 spec. Its technology and interior equipment were adopted by the
European BMW 7 Series Executive models. On the outside, this 745i was
identifiable by hubcaps bearing the old BMW Motorsport logo, while inside the
car only the speedometer featuring the letter M and the Motorsport stripes
indicated that the engine nestling underneath the bonnet was anything out of the
ordinary. Boasting a top speed of 241 km/h, the South African BMW 745i was only
marginally slower than the almost 300 kg lighter BMW M5. By May 1986, only 192
models of this rare breed had left the factory.
The US market also offered a special variant of the BMW 7 Series, known as
the L7. Even among BMW connoisseurs, this model designation is generally only
familiar from the third-generation 7 Series, when the car was offered to the
Arab and Asian markets with a longer wheelbase and an inserted centre section.
However, in autumn of 1985 an L7 model appeared on the American market in which
the L stood for “luxury”. This model corresponded in almost every respect to the
European BMW 735i Highline, although it offered a range of additional standard
equipment such as a driver airbag, electric sliding roof, air conditioning and
heated seats.
But the BMW 7 Series not only stood for dynamism and luxury; it was always a
byword for innovation, too. The early 1980s, for example, saw the inception of a
pioneering experiment: in collaboration with the German Test and Research
Institute for Aviation and Space Flight (DFVLR), a BMW 735i and 745i were
converted to so-called bivalent operation on either liquid hydrogen or petrol.
By then BMW had already recognised the environmental credentials of hydrogen and
the fact that, as a secondary energy source, it offered virtually unlimited
long-term availability. The systematic pursuit of this path would lead, after
almost 25 years of development work, to the launch of the first hydrogen-powered
production model in late 2006: the BMW Hydrogen 7.
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