The Dodge Challenger SRT Hellcat's 707-horsepower 6.2-liter supercharged V8 continues to be the output leader in the muscle car segment, even as competitors like the Camaro ZL1 start to nip at its heels. Hennessey is happy to serve owners who are afraid to lose a stoplight drag race, though. In a new video, the tuner gives a taste of what it can do to the Hellcat by lining a stock example up next to a Challenger with the firm’s HPE850 kit, which technically boosts output to 852 hp (653 kilowatts).

It’s not shocking when the HPE850 beats the stock Challenger – after all, Hennessey’s kit adds an extra 145 horsepower. The tuned version doesn’t pull ahead immediately, though. The pair remains side by side for the first several feet, but the aftermarket mods eventually let the yellow coupe pull ahead. This clip is also a joy for the ears because you can hear twice as much supercharger whine from the Hellcats. Plus, Hennessey stages a double burnout as an extra treat.

Hennessey doesn’t add many parts to get the extra power from the Hellcat. The HPE850 package’s mechanical upgrades include new ECU software, high-flow air filter, port-matched throttle body, and an upgraded lower pulley, which increase boost by 1 to 2 pounds per square inch. There are also small aesthetic improvements like Hennessey badges and the company’s logo embroidered on the headrests.

Hennessey also offers two even more potent tunes of the Challenger Hellcat for customers who crave more power. The HPE1000 Supercharged boasts 1,012 horsepower and the HPE1000 Twin Turbo / Supercharged produces 1,032 hp.

Source: Hennessey