The 10 Most Unusual Engines of All Time.

Most car engines today are pretty similar. Even the ones we’d call different, like Porsche’s flat-sixes or Fiat’s new two-cylinder, follow tried-and-true engineering maxims that have dominated the industry for the past 50 years. But not every car manufacturer plays by the rules when designing engines. Some of the nonconformist engines are just weird enough to raise an eyebrow, but a small number are completely off-the-wall, shirt-eating, stranger-hugging insane. Sometimes there was a method to the madness, such as trying to improve efficiency. Other times, it was clear the inmates got the run of the engineering department. And we’re just fine with that.

To put together our list of 10 crazy car engines, we followed some rules: production passenger-vehicle powerplants only; no racing mills or one-off experiments, because those are weird by definition. We also left off engines that distinguish themselves solely by being the first or largest of something. That’s because the goal here is to emphasize the kind of crazy engine design that makes your brain hurt.

So let’s fire em up.