The Jeep Grand Cherokee Trackhawk is one of the most extreme SUVs ever made, thanks to its 6.2-liter supercharged Hellcat V8 engine that produces a monstrous 707 horsepower and 645 lb-ft of torque. Most owners would probably agree that having that amount of power in an SUV is excessive. Hennessey, however, disagrees, and is now offering a HPE850 Upgrade package for the high-performance SUV. As the name implies, the upgrade adds an additional 145 ponies, bringing the total output up to 852 horsepower and 845 lb-ft of torque.
To achieve this, the tuning company has upgraded the SUV's software, attached a high-flow air induction system, and increased boost to 14 psi via a lower pulley upgrade. As usual, Hennessey hooked up the upgraded SUV to a dyno to back up its claims. Surprisingly, the tuner opted to switch the Grand Cherokee Trackhawk to rear-wheel drive during the dyno test.
Nevertheless, factoring a 20 percent drivetrain loss the souped-up SUV sent 722 hp and 655 lb-ft of torque to the wheels while running on Shell V-Power 93 octane pump fuel. That translates to a total of 866 hp and 786 lb-ft of torque at the crank, but it's possible the result could have been different with AWD enabled. Compared to the stock Hellcat-powered 2018 Jeep Trackhawk, the Hennessey Jeep makes 135-wheel hp and 89 wheel torque over stock. If the HPE850 upgrade package still isn't enough for you, it probably won't be long until Hennessey ups the ante and offers a HPE1000 version with over 1,000 hp on tap. Watch this space.