16: Acura Vigor
The original Acura lineup was a departure from other Japanese luxury car makers like Lexus. Take the Acura Vigor, the full-size sedan offered by Acura. Instead of utilizing a V8 engine, like the competition, Acura decided to go with a five-cylinder setup. The driving characteristics were unique, to say the least, albeit a bit different (via Motor Trend).

Unfortunately, the Vigor design never caught on with consumers. The five-cylinder engine setup was odd in a new segment. Luxury car shoppers were still used to going for the enormous V8 engines or supercharged V6 powerplants. The Vigor with its unique look and feel simply didn’t catch on in the way Honda had hoped.