The Viper only makes 650 horsepower, but it's also much lighter.

Hennessey isn’t known for slow. That’s a speed for those other guys. The Texas tuner does a lot of work to wring every last bit of power out of a variety of vehicles – from SUVs to sports cars. The company is famous for its HPE packages – which stand for Hennessey Performance Engineering – that bundle all your performance goodies together. To show off its upgraded 850-horsepower (633-kilowatt) HPE850 Ford Mustang Shelby GT350R, Hennessey pitted the high-powered pony against a stock snake – a 650-hp (484-kW) Dodge Viper.

The race isn’t a blowout like you’d expect. While the GT350R has more horsepower, it’s also heavier than the Viper. Just look at the size difference between the two in the video as they round the corner before taking off from a rolling start. The Mustang looks massive. However, while the two stay close to one another at the beginning of the race, the Viper is no match for the Mustang’s increased horsepower. Near the end of the race, you can see the Mustang driver lay off the accelerator only to press back into the gas. It’s here you can see how much more power the Mustang makes, quickly pulling away for a second time.

The Mustang is far from stock. Looking at Hennessey’s product page, the HPE850 pack for the GT350 adds a high-flow throttle body, fuel injectors, heat exchanger, and air induction system, and a 2.9-liter supercharger. Hennessey claims the tuned Shelby hits 60 miles per hour from a standstill in 3.3 seconds while rocketing through the quarter-mile in 10.8 seconds at 133 mph. It’s no slouch. The tune increase torque to 673 pound-feet (912 Newton-meters).

In the video, Hennessey says the race is part of its benchmark testing for the Viper, likely in preparation for a new, more powerful HPE package. Right now, Hennessey offers the Venom 700R upgrade for the Viper that boosts power to 735 hp (548 kW). That package alone is enough to rocket the Viper to 60 mph in 2.9 seconds. Imagine if the Viper had an HPE850 package available. Either way, America wins.

Source: Hennessey via YouTube