The 1980s were a time of excess, when Thatcherism pushed for a free market, greed was good (in some eyes), power suits hung off padded shoulders, lunches lasted long into the night and car phones and Filofax were the ultimate accessories to perch on a wine bar counter.
Against this backdrop, BMW was ruled by engineers, and they usually got their way. Leading the development of powertrains for the German car marker was a Dr Karlheinz Lange, and the good Dr was not content for BMW to merely rub shoulders with its V12-powered competitors at the top of the luxury saloon car market. Oh no. Dr Lange wanted a new engine that would be as much a status symbol as any ski chalet, sailing yacht or Eurocopter – a V16.
The trouble was, nobody else at BMW was asking our Dr friend to create a 16-cylinder engine. But Her Lange was nothing if not resourceful, so he approached Adolf Fischer, one of BMW’s seasoned engineers, and the duo conspired to build an experimental 7 Series, the likes of which had never been seen before. To this day, it ranks as one of the most extreme demonstrations of skunkworks engineering at BMW.
Fischer had previously spearheaded the development of the M70-generation BMW V12 engines found in the E32 750i and E31 850i models. To fulfil Dr Lange’s fantasy, though, the German brand’s flagship twelve-cylinder engine simply wasn’t going to cut it.
In July 1987, Lange asked that an all-new flagship engine be developed at double-quick speed, with Fischer answering the request by saying: “The engine will be under the Xmas tree.” To satisfy the brief, Fischer set about creating a new, all-conquering powertrain which would go on to be codenamed “Goldfisch” (Goldfish), given the crude appearance of the eventual running prototype.
Using the design of the existing M70 5.0-litre V12 as a base, two additional cylinders were added to each bank, creating a V16. The new engine retained the 60-degree V design from its smaller sibling, receiving a new extended cylinder block cast using silicone aluminium, along with new heads fitted with a single chain-driven camshaft. The displacement was increased to 6651cc (6.7-litres), and the new engine measured in at nearly 30cm longer than the V12 on which it was based.
Thanks to this significant increase in capacity, the Goldfisch V16 produced 402bhp. While this may not sound like a huge figure by modern standards, remember this was in 1987, a time when BMW’s most powerful flagship V12 engine produced a paltry 296bhp.
Once development of the engine was completed early the following year, it was fitted into the nose of an E32 750iL. To accommodate the larger dimensions of the V16, the car’s cooling system had to be re-engineered by mounting the radiator in the boot. To keep it cool, a straightforward approach was adopted with the addition of a large pair of gill-like air intakes – hence the ‘Goldfisch’ nickname – to the car’s rear quarter panels to channel air directly to the radiator, along with a full-width air vent beneath the boot lid to expel hot air.
To complete the drivetrain, a six-speed manual, shared with the 8-Series, was fitted to get all of the power to the rear wheels. Yes, not only did the Goldfisch hide a vast V16 engine under its bonnet, but it also got a hint of driver appeal with a manual gearbox.
At the time, the development of a V16 powertrain was a feat unmatched by Audi and Mercedes. Germany’s trio of powerhouse premium brands were trying to outdo each other with ever-increasing levels of lavish luxury and excessive engineering. So a V16 producing 402bhp would have left BMW’s nearest rivals trailing. Audi’s best effort at the time was its flagship V8-powered Typ 4C saloon, which could only muster 247bhp from its 3.6-litre engine. While Mercedes wouldn’t launch its new 402bhp M120 6.0-litre V12 engine until the start of the next decade with the W140-generation S-Class in 1991.
Of course, for all the excitement that must have surrounded the project, the V16 engine was never intended for production. While BMW did commence testing of the powertrain in May 1988, the official line from the company states that “the engine was never intended for use in a series vehicle,” making it a demonstration of what was possible rather than the future direction of its powertrains.
Just a few short years later, though, BMW’s quest for V16 power was rendered redundant. In 1992, the arrival of the flagship 850CSi introduced a new 5.6-litre S70B56 V12 engine. It produced 381bhp, a power figure close to the larger V16 Goldfisch unit that also required no costly reengineering to make it fit in the nose of the E31 8 Series coupe.
While an uber V16-powered 7 Series with a manual gearbox sounds like an all-conquering Autobahn express, the reality for Dr Langer and his colleague Fischer was that there was no chance of it ever making production in that generation of 7-Series.
Due to its increased size, the V16 wouldn’t fit in the saloon’s platform without substantial engineering changes, something that could never be justified given the tiny potential market for such a profligate car. After all, at autobahn speeds, it’s reported that the V16’s fuel economy would have been in the region of 9mpg, and then there’s the potential cost…
If a V16-powered 767iL had made it into showrooms, its price tag would have surpassed the £57,100 (equivalent to £151,000 today) cost of the regular 750iL by an eye-watering margin, limiting its appeal to all but the wealthiest buyers.
After this brief exploration of what was potentially possible with a V16 powertrain, word reached Dr Lange that the BMW board was content with its flagship V12 engine and any subsequent evolution. Sure enough, it would go on to morph into the 600bhp twin-turbocharged monster we know today. The V16 remained a pet project.
And as for the 750iL Goldfisch, well it now resides in the BMW Classic collection, an example of what happens when engineers are given a free rein during one of the most hedonistic eras of recent times.