If you’re thinking about a 2017 ZL1 Camaro, you may want to consider Hennessey Performance Engineering’s recent engine upgrade for the model. The tuner is calling the revised powerplant the HPE850. That’s 850 for—yes—horsepower.

Actually, Hennessey details the rating as high as 858, but that’s considering the manual transmission as default. Torque comes in at 830 lb-ft with a manual gearbox. An automatic transmission will lower the numbers to just about 850 on the nose.

What will the upgrade yield in kinetic performance numbers? Hennessey claims the Camaro ZL1 equipped with their HPE850 engine will launch to 60 in just 2.7 seconds. They claim, further, that the upgraded ZL1 will jaunt to a quarter mile in 10.4 seconds, hitting 135 miles per hour along the way. Finally, they give a top speed for a ZL1 with an HPE850: 210 miles per hour. That kind of performance should satisfy even the more jaded speed-hounds out there. 210 in a passenger car is serious, hair-raising business.

The ZL1 upgrade includes all kinds of improvements to fuel flow and air flow, including high-flow cylinder heads, catalytic converter, and air induction system, as well as long-tube stainless headers and midpipes, new valve springs and intake and exhaust valves, and a camshaft upgrade. There are plenty of cosmetic flourishes, too, including interior and exterior plaques and emblems.

The HPE850 Camaro ZL1 upgrade will be offered on a limited basis by Hennessey, with only 100 available. The upgrade comes with a 2 year/24K mile warranty.