Hennessey’s HPE1200 upgrade for the Dodge Demon puts down some insane power number in rigorous dyno testing.

We already know that the Dodge Demon is a fast car. When it was being made, Dodge advertises a power figure of 840 ponies with 770 lb-ft of torque. That was assuming 100 octane racing fuel, of course, and it’s quarter-mile time of 9.6 seconds seemed more theoretical than practical, but there was no denying how powerful the Demon was.

Hennessey scoffs at Dodge’s attempt at power. They see the Demon as a starting point, not an endpoint. With Hennessey’s help, the Demon can become something even more powerful--perhaps even the most powerful drag racer ever made.

Cue scary music.

Hennessey offers two upgrades for Demon owners: the HPE1000 and the HPE1200. In keeping with their nomenclature, the number represents horsepower at the crank, true gearheads know that true power is measured at the wheels. That’s why Hennessey tests there HPE1200 Demon on their Dynojet to get an accurate reading of rear-wheel power.

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The Demon still comes with its impressive 6.2-L HEMI V8, but the puny 2.7-L supercharger has been tossed out in favor of one over twice as large: 4.5-L. There’s a bunch of other tuning done, like a new throttle body, upgraded fuel injectors, and a higher flow high-flow air induction system, which all combine to push the Demon to the ragged edge of performance.

After a few moments of extreme engine noise and a supercharger whine that could literally wake the dead, Hennessey posts the dyno performance. Peak horsepower is 1,013 hp at about 6,500 RPM, while peak torque is 954 lb-ft. Torque is actually pretty constant from 2,600 RPM to 5,500 RPM, never dipping below 900 lb-ft until the very end.

Keep in mind that these numbers are at the wheel. So far, Hennessey hasn’t disclosed the engine horsepower rating but remember: HPE1200 means 1,200 hp at the crank.

This also gives us a good idea of what kind of power losses the HPE1200 gets. About 10% is a good rule of thumb for cars, and the HPE1200 Demon loses about 15%. Then again, nobody will ever accuse Hennessey of making efficient vehicles.

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