Considering the new Viper is yet to be delivered, it's not clear if Hennessey is basing those numbers on a different engine to the latest 8.4-liter unit or if they're just estimates. However, given the performance of previous Hennessey upgrades, including the custom Venom GT supercar, Hennessey is certainly capable of drawing big power numbers from American engines.
For the new Viper, Hennessey adds a custom twin-turbocharging kit consisting of a pair of ball bearing turbos, a front-mount intercooler, a stainless steel exhaust kit, upgraded engine internals, a new fuel system, a high-flow intake and an upgraded engine management system.
With all this on board, and your power levels now hovering around 1,120 horsepower, Hennessey says you’ll be able to accelerate from 0-60 mph in just 2.7 seconds and pass the quarter mile in 9.7 seconds at 152 mph.
The chassis of the latest Viper is certainly capable of handling more power than the stock 640 horsepower, but to handle close to double the output the car was originally designed for, Hennessey adds a new aerodynamic package, light alloy wheels, adjustable coilover suspension, and a rear differential cooler.
If all this sounds a bit over the top for you, Hennessey will also be offering a milder 700R package with ‘just’ 725 horsepower on tap.