What's the Most Unusual Engine/Car Pairing Ever?

Mercedes-AMG just widened some eyes by dropping a four-cylinder engine into the AMG GT. It's the same engine that powers the SL43 AMG, only with a few extra ponies. Prior to its new four-pot, the AMG GT was exclusively powered by snarly, violent V8s, the sort of engines that fit its muscular design. Now, though, there's an entry-level version with a coarse, gravely 2.0-liter four-cylinder that seems unusual in the six-figure sports car, even if it does benefit from some of AMG's Formula 1-derived turbo wizardry. That led us to wonder what other sort of unusual engine/car pairings there have been over the years, for better or worse.

Of course, the automobile has been around for over 100 years, so there are bound to have been examples of the phenomenon. The 6.8-liter V10-powered Ford F-150, Volkswagen Touareg V10, and I'd even argue the new, V12-equipped Ferrari Purosangue all come to mind. But the car that I think of most is the B5-generation (1997-2004) Volkswagen Passat W8.

What makes the Passat W8 so unusual? For starters, it's a W8, not a V8, which boggled the mind of most casual car enthusiasts back in its day. The 4.0-liter W8 was essentially two narrow-angle 15-degree VR4s sandwiched together to share the same crankshaft, similar to how the Bugatti Veyron's W16 and Bentley's W12 worked (both of which are also VW Group products). Passat W8 owners liked to joke that they had half a Bugatti engine in their car. They wished, though, as the Veyron made over 1,000 horsepower and the Passat W8 packed just 275 hp and 273 lb-ft of torque.

Power figures aside, it was weird to see an eight-cylinder engine in a Passat, which was supposed to be a simple, affordable midsize sedan. Even weirder was to hear it. A Passat, of any generation with any engine, doesn't sound interesting when it drives by—it just sounds like any other normie car. But the Passat W8 had the rumble of something exotic. Its W8 engine made a delicious, performance car-growl right from the factory. You could shame a '90s Corvette V8 noise with a sensible little sedan, and there's no way that ever got old for owners.