Hennessey Performance doesn’t need an endless teaser campaign to introduce its products. Four-digit horsepower numbers tend to create hype all on their own. With its sights trained on the chest of the Dodge Challenger SRT Demon, Hennessey announced The Exorcist, a Chevrolet Camaro ZL1 that the aftermarket company claims makes 1000 horsepower at 6400 rpm and 966 lb-ft of torque at 4400 rpm. That’s more than we expect the factory-backed Demon to produce, but the Hennessey upgrade comes at a hefty price: The Exorcist’s additional equipment will command, at the very least, $55,000 on top of the ZL1’s $63,435 starting price.
The Exorcist enters the scene as yet another monster from Texas-based Hennessey, which also counts among its wares 700-plus-hp Ford Mustangs, 1000-hp Cadillac CTS-Vs, and 1032-hp Challenger and Charger Hellcats. So,  while such staggering output numbers aren’t necessarily anything new from the tuner, when coming from a vehicle that logged 1.04 g during our skidpad testing, 1000 horsepower seems a little more special.
The Exorcist still packs the LT4 V-8 that makes 650 horses in the regular ZL1, but bolstered through a variety of upgrades. It has a higher-flowing supercharger that makes a claimed 14 psi of boost, a new intercooler, and a new camshaft. Airflow was further improved with long-tube stainless-steel headers and a high-flow induction system. There is of course a custom tune for the engine management soft...