From the very beginning the Hennessey venom GT was create to fight against the Bugatti Veyron. After the Molsheim based carmaker announced that will produce a new version of its hypercar the Americans comes with a second generation of the Venom GT. 
The 2013 Hennessey Venom GT2 will use the same twin-turbo 7.0 liter V8 unit that will get a power hike to 1.500 hp. The engine will be connected to a manual six speed Ricardo gearbox or to a new seven speed paddle shift transmission. 
Even though the performance figures were not released, the model will be quicker thanks to its power to weight ratio (more than 1hp/kg). If you already forgot, the 2012 Venom GT needs only 2.2 seconds to accelerate from stand still to 62 mph and the top speed is clocked at 272 mph (440 km/h). 
On the outside the new Venom GT will borrow the same carbon fiber body. The American producer decides to replace the doors while the headlamps and the hood will be redesigned.

Source: Hennessey