These days, you can only find a 16-cylinder engine in Bugatti's multimillion-dollar Chiron and even 12-cylinder engines are falling out of vogue. Earlier in the previous century, cars carrying cylinder-rich engines were more common—but over time, cost, complexity, and ever-more-powerful engines with more normal cylinder counts rendered them fairly unnecessary. Luckily, BMW didn't get that memo even in the late 1980s, when it created a V-16-powered 1987 BMW 750iL, which it nicknamed "Goldfisch." No need to break out the translators—as you've probably surmised, that's "goldfish" in German.

Both in name and concept, the 750iL Goldfisch project was simply a "Why not?" moment for BMW. (The silly-sounding name is a result of the gaping, gill-like intakes extending from each of the 7 Series' rear quarter panels.) It was born after a small group of engineers within BMW secretly discussed the possibility of building an engine even bigger than the 750iL's regular-production V-12. Apparently, the group settled on the number 16 for the new engine's upper-limit cylinder count; the lower limit, it was determined, was a baby three-cylinder version of the same engine. (We know, way less interesting. ) The project was undertaken to show the versatility of BMW's engine family at the time.

The 6.7-liter V-16, internally referred to as ED-173-1, was pretty much BMW's normal 5.0-liter V-12 enlarged with another four cylinders added to one end. It was first put on a dynamometer in January of 1988, where it was found to make "only" 406 horsepower. Although that power, back then, was truly incredible, these days there are four-cylinder engines in regular production that make as much (and the quad-turbo W-16 in Bugatti's Chiron makes up to 1,500 horsepower). Anyway, the V-12 in the normal 750iL made 296 horsepower, meaning the addition of a third more more cylinders added about third again more horsepower. Talk about a linear scale!

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Fitted to an E32-generation 750iL, the mighty V-16 engine necessitated serious structural changes to the engine bay. Of course, the big mill was heavier than the stock V-12. It also was physically bigger, so much so that radiators couldn't fit with it under the 7 Series' hood. So, BMW moved the radiators to the sedan's trunk—necessitating those huge, odd air intakes behind each rear door and inspiring the 750iL concept's nickname. Extra slots in the trunk also vented hot air out of the car's rear.

Wouldn't you know it, BMW decided not to put the Goldfisch into production. Allegedly, the automaker was keen to avoid some kind of engine arms race with Mercedes—and chose de-escalation by sticking with the 750iL's V-12. We kind of wish the two sides weren't so diplomatic. Either way, the lone example of the Goldfisch lives in BMW's heritage collection to remind everyone that BMW could build such an engine if it wanted. Not that it would, but it definitely could. It won't, but c'mon.