Internal combustion engines are far more complex than electric motors, and it’s correspondingly more difficult to make them produce a lot of power. Yet, despite the rise of electric vehicles (EVs) like the 2011 horsepower Lotus Evija—a stunning example of EV potential—the most powerful cars of the near future may indeed be electric. Still, remarkable outputs have been achieved with engines fueled by petrol or diesel, especially in the United States.
In this article, we’re spotlighting 20 of the strongest internal combustion engines ever created in the US, all of which powered cars or non-commercial trucks sold to the public for road use. That means no 11,000-horsepower Top Fuel dragsters here—just street-legal powerhouses. A prime example? The 2023 Dodge Challenger SRT Demon 170, boasting a supercharged 6.2-liter V8 that pumps out an incredible 1,025 horsepower on E85 fuel, proving petrol engines still have fight left in them.
These engines are listed in ascending order of their quoted outputs, with a note of caution: the shift from gross to net horsepower in 1972 complicates comparisons across eras. To keep things fresh, only the most powerful unit from any engine family is included. This isn’t a traditional top 20, as many engines are skipped if they’re outdone by close relatives, but it ensures variety—and who doesn’t love a bit of variety?
