For the latest classic car news, features, buyer’s guides and classifieds, sign up to the C&SC newsletter here
If the Neue Klasse represented the start of BMW’s post-war return to profits and success, then the first 7 Series, which arrived in 1977, seemed to be the final confirmation that the process was complete.
Strategically, it was an important car. This was the first time that BMW had demonstrated the confidence to truly challenge the Mercedes S Class head on with a luxury saloon of comparable ambition.
The E3 was an excellent car, one of Europe’s great saloons, but somehow BMW’s marketing men had never quite allowed it to square-up to the biggest and the best that Mercedes-Benz had to offer.
The 7 Series changed that perception, carefully shifting the emphasis towards refinement and luxury but without sacrificing driver appeal.
A more grown-up saloon than the outgoing E3, the E23 7 Series had been in development almost as soon as its predecessor had gone into production.
The first mock-ups were built in 1970 and prototypes, disguised as E3 3-litre saloons, were running by ’73. As early as 1974, Paul Bracq had finalised the styling of the new model. It looked bigger and more imposing than the cars it replaced – in fact the E23 was 6¼in (160mm) longer, had 4in (102mm) more wheelbase and a wider track all round – and seemed almost a class above.
It was also able to usefully place itself definitively upmarket from the 5 Series. Bigger-engined E12s tended to tread on the toes of the E3 range in its run-out years, which is why Munich tried to dress up its flagship with longer-wheelbase, larger-engined and more luxurious models (such as the 3.3Li) to demarcate the ranges.
The 7 Series also completed the BMW line-up for the ’70s, with a strong family likeness to the 3, 5 and 6 Series cars. The aim was more space, more refinement and greater stability. Yes, there would be more weight – the bigger body was stronger and more crash resistant – but performance had at least to be maintained.
The chassis was the familiar BMW mix, but with technology borrowed from the 6 Series plus many subtle refinements and improvements: double-jointed anti-dive MacPherson struts, less offset in the steering geometry and a stiffer subframe for the rear axle which was effectively a refinement of the E3’s semi-trailing arms.
The same pump powered the hydraulics for the brake servo and the steering. The shell, with 11% more glass area than before, had stronger roof pillars and a roll hoop. It was designed around proper ventilation and climate control, big electric mirrors, central locking and all the other stuff we now take for granted even on cheap hatchbacks.
Even the basic 728 had speed-sensitive power steering but on the other hand it was surprising what the Bavarian firm still charged extra for: electric windows and air-conditioning were not even standard on the range-topping 733i – nor, for that matter, was automatic transmission.
Separate, electrically adjustable rear seats were among the more exotic options and, later, the 7 Series would pioneer heated door locks, rear sunblinds and in-car phones. More importantly, anti-lock brakes made their BMW debut on the E23 in ’78.
BMW’s nine-year-old straight-six remained at the heart of the 7 Series: V8s and 4.5-litre V12s were discussed (the prototype is even shown in the brochure, along with the reasoning behind its rejection). Yet, in the aftermath of the fuel crisis, the existing six-pot, reworked to optimise economy without losing power, had a more rational, thrifty image than the V8s that formed the core of Merc’s S Class range.
Initially, there were two carburettor models – 728 and 730 – and the fuel-injected 733i flagship, but by the end of the ’70s the E23 range would be exclusively injected, the carburettor engines having proved thirsty. The 735i usurped the 733i (re-badged 732i) as the range-topper in 1979, offering a five-speed overdrive manual ’box and 218bhp.
The new saloon quickly outstripped the E3 range in sales, shifting 20,000 in ’77 and 35,000 in its first full year. The UK was always a healthy market where there were six-month waiting lists. The E23 ran through to 1986 with only one facelift in ’82, when the nose was reworked to improve aerodynamics. Fully optioned ‘Highline’ 735s and a four-speed ‘overdrive’ automatic were added in ’84.
From 1980 onwards, left-hand-drive markets had been offered the turbocharged 745i as the fastest and most luxurious 7 (see panel) yet, as far as the UK was concerned, the 733i represented the ultimate until the 735i appeared. ‘Our’ black 1977 733i is a low-mileage example owned by BMW.
Bracq’s bluff shape, closely related to his 6 Series, doesn’t have the neat, airy, late-’60s appeal of the handsome E3s. Shark-nosed and slab-sided, it seemed to date quickly and made few concessions to streamlining, but it has the right indomitable presence. Large areas of chrome trim and hefty bumpers make it a car that somehow bridges the ’70s and ’80s. It certainly looks more impressive now than it did a decade ago.
Outside, the black paint has a deep shine you could almost dive into, the doors feel hefty and the elaborate seals bear testimony to BMW’s commitment to making this its most refined and best-quality saloon ever.
Step inside and you instantly appreciate how BMW was already setting the standard in facia design. Clear instrumentation – one sheet of non-reflective covering across the instruments – rational switchgear and the curving centre console grouped around the driver created an atmosphere that put most others to shame in terms of the quality of materials.
You could tailor an optimum driving position because the seat base could be adjusted for height and the steering column for reach. The seats are solidly built, firm and luxuriously trimmed in brash avocado velour, a reminder that few felt the need for leather in the ’70s and most liked colour schemes that matched their bathroom suites. Maybe this was the 733i that BMW couldn’t sell, so it had to be kept?
The big rear headrests suggest executive-style comfort in a deeply windowed and well-ventilated cabin. A first-aid kit in the rear armrest shows the attention to detail that delighted BMW owners and won the model so many friends. Options on this car include power windows, a generously sized electric steel sunroof and air-conditioning.
Today, the panel of lights to the left of the steering column has the slightly cheesy feel of a Sinclair Spectrum but was a wondrous innovation in 1977. Standard on the 730 and 733i, the unit monitors all fluid levels, lights and brake linings – the ‘TEST’ button is used to check the panel itself is working.
Under way, the 7 Series has characteristics that E3 or even 2002 drivers would recognise. Sitting quite high on firm, broad seats, you have commanding vistas from all angles, if not quite the slim-pillared vision afforded E3 drivers.
The canted straight-six, with its purposeful intake manifolding and plenum chamber for the Bosch electronic injection neatly presented under the front-hinged bonnet, feels sharp and lusty. It revs eagerly or delivers strong, steady torque for smooth progress.
A manual gearbox in a car such as this would be unthinkable now, but in the ’70s a significant number of big saloon drivers still wanted to self-shift. It’s a surprise to find only four speeds, but the well-spaced ratios make the most of the free-revving straight-six, its howl being only mildly restrained.
Using 6400rpm in third would take the 3550lb (1610kg) 733i to 100mph and it will cruise comfortably on the autobahn at 120mph. The clutch is smooth, middleweight and totally forgiving, so even town driving is vice-free and no real chore. The car dispatches its four gears with effortless authority.
The change has a short action, slightly notchy in the lower gears but that should free up with use and miles: this car is virtually new, after all. First and second whine a little yet it seems a small price to pay for the sense of involvement and control the manual gives you: it reminded me why I’ve never really got on with automatic BMWs.
The chunky, four-spoke steering wheel and instinctive stalk controls make you instantly at home. The ZF recirculating-ball power steering must have been among the best: a slight vagueness around the centre, but faithfully consistent as you apply lock, and never over-light or lacking in feel.
Where the quicker E3 cars had promoted extrovert driving, the 7 Series was designed to feel more neutral to understeer, with the opposite condition only to be discovered by those who really went in search of it. Even so, the 733i was among the most nimble of big cars and its relative lack of wallow or roll still encourages you to drive it enthusiastically. The front floats a little yet the ride is all about firm comfort with a fair amount of road noise and tyre rumble thrown in.
The market for luxury saloons recovered surprisingly rapidly after the early ’70s fuel crisis, so a big flagship BMW – slightly less ostentatious and younger in image than its Mercedes equivalent – was well-placed to cash in on the continuing appetite and rising awareness of West German build quality, reliability and performance.
In this burgeoning luxury sector, buyers were not so sensitive to price and profit margins were higher – the fact that the cars were expensive only seemed to add to their impression of excellence. Jaguar built cheaper, more graceful and refined cars but reliability problems, born of industrial strife, were testing customer loyalty to the limit. You can only wonder at how many XJ buyers the BMW poached – for good.
I’m not so sure the 7 Series really trumped the S Class, but model-for-model the E23 range was faster – and cheaper – than the equivalent W116 Mercedes, so BMW’s engineers must have felt vindicated. Although it lacks the charisma of the E3, it’s easy to see how the 7 Series closed the credibility gap between Munich and Stuttgart.
So desirable 30 years ago, it fulfils the essential luxobarge criteria of its current desirability being inversely proportional to its aspirational status when new.
Sheer rarity – when was the last time you saw a nice, or otherwise, E23? – will probably raise its intrigue factor before long. Maybe it already has, but if I come across any more 733is with 61km on the clock, I’ll let you know.
Images: Gudrun Muschalla
BMW 733i FACTFILE
- Sold/no built 1977-’86/285,029
- Construction steel monocoque
- Engine front-mounted, iron-block, alloy-head sohc 3210cc ‘six’, with Bosch L-Jetronic injection
- Max power 197bhp @ 5000rpm
- Max torque 206Ib ft @ 4300rpm
- Transmission four-speed manual or optional three-speed automatic, driving rear wheels
- Suspension: front MacPherson struts rear semi-trailing arms, coil springs, telescopics; anti-roll bar f/r
- Steering ZF power-assisted recirculating ball
- Brakes servo-assisted discs all round
- Length 15ft 11 in (4858mm)
- Width 5ft 11in (1803mm)
- Height 4ft 8 in (1429mm)
- Wheelbase 9ft 2in (2794mm)
- Weight 3550lb (1610kg)
- 0-60mph 8.3 secs
- Top speed 128mph
- Price new £12,699
- Price now £5-20,000