Hellcat is a trim level and badge that's only ever put on the fastest cars that Dodge can build. Nowadays, there are two that stick out, the Charger Hellcat and the Challenger Hellcat. Both come with a similar engine - a massive 6.2-liter supercharged V8. Although, they have been tuned slightly differently for both cars. In the Charger, the top-most Hellcat variant spits out 797 horsepower. Meanwhile, with the Challenger, the fastest Hellcat version has a whopping 807 horsepower. The latter is officially the most powerful production V8 engine. For a Hellcat, outrageous horsepower, that loud supercharger whine, and lots of tire smoke is the main appeal of Dodge's fastest muscle cars.