Did you buy a Dodge Challenger SRT Hellcat? Good for you! That means you have an entertaining 707-horsepower mean machine parked in your driveway. A question though, if we may. Do you ever wish you had more horsepower on tap?As you might expect, Hennessey Performance has a power package for you.

The Challenger Hellcat HPE850 receives a fresh tune, new pulleys, and breathes a bit more easily. That alone is enough to see output rise to 852 horsepower and 845 pound-feet of torque. That power figure is quoted as being at the engine, and John Hennessey quotes 730-740-hp to the wheels.

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The particular HPE850 in the video above also gets long-tube headers, exhaust cutouts, and a set of Nitto drag radials at the rear. This means it should hook up quite well and also be deliciously loud. With those electronic cutouts, however, you can also quell the noise should you tire of the car constantly shouting at you.

Of course, Hennessey has had this package for awhile. In this video, John Hennessey drives the HPE850 around his grounds and dragstrip and reviews the car for his potential customers. It's a review of both his modifications and the stock Hellcat, which Hennessey describes as driving your living room couch with a jet engine. Hennessey also makes a few speed runs in the car, and a hard launch that works better at 3,000 rpm than it does at 3,500 rpm. That's quite a bit higher than you can launch a stock Hellcat, and it's thanks to the drag radials.

Hennessey has prepped plenty of bonkers builds. There's a 1,032 twin-turbocharged Hellcat and Hennessey also promises that 1,500 horsepower will be available when it gets its hands on the Dodge Demon. Compared to those cars, the HPE850 seems downright reasonable.