Ford has something special on its hands in the Shelby GT350. Make it the R version, and ratchet up the degree of special a few ticks more. One of the best parts about the car, besides its wonderful on-track performance, is the noise it makes. The 5.2-liter V-8 engine sings its flat-plane-crank song to all who will listen, and that will be a lot of people, because this thing is loud. Hennessey has now, as you might expect, made the GT350 even louder and more powerful.

The upgrade package is called the HPE850. If you have a GT350 or GT350R and you add this package, you're going to feel quite the jump in power. In stock guise, the Shelby GT350 sees 526 horsepower and 429 pound-feet of torque. Hennessey has dyno-tested the modified car and logged gains of 311 horsepower and 193 lb-ft of torque at the wheels. That's almost an entire V-6 Mustang's worth of extra power at the rear wheels.

So Hennessey now offers a GT350 that's producing 858 horsepower and 673 lb-ft of torque. At the rear wheels, this car is making 787 horsepower. Hennessey says the car will run from 0 to 60 mph in just 3.3 seconds and rip down a quarter-mile in just 10.8 seconds.

The Texas tuner is able to achieve these power gains thanks to the addition of a 2.9-liter supercharger. Buyers also gain a high-flow throttle body, high-flow fuel injectors, the Boost-a-pump fuel-pump upgrade, a high-flow air induction system, and fresh gaskets & fluids. Your car will wear a number plaque with its own modification serial number. Some exterior badges tell others of your potential for stoplight-to-stoplight supremacy. Finally, all parts get a two-year, 24,000-mile warranty.

We don't know how much it will cost to upgrade your GT350 this way, but you're certainly getting a heck of a lot more power for the price.


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