With 760 horsepower and 625 lb-ft of torque from its 5.2-liter supercharged V8, the Ford Mustang Shelby GT500 is not exactly lacking in power. In fact, it's one of the best Mustangs ever made, and all that power is put down to the ground remarkably well. But what if you want more? Hennessey Performance Engineering has been modifying America's V8 monsters for years, and it always takes the latest and greatest that Detroit has to offer and gives it more horsepower than it needs - not that we're complaining. Now it's done the same with the GT500, giving it a 58% boost over factory engine output for a tire-melting total of 1,204 hp and 902 lb-ft. Say hello to the Hennessey Venom 1200.

That output makes the GT500 - which is the most powerful factory Mustang to date - "one of the most powerful muscle cars Hennessey Performance has ever produced." The enormous output was achieved by fitting a higher capacity 3.8-liter supercharger, a high-flow induction system, new fuel rails and injectors, and an air/oil separation system. To ensure reliability, Hennessey also upgraded the fittings, lines, belts, and tensioners, and the dual-clutch automatic transmission was also recalibrated to cope with the added strains of Bugatti Veyron-beating power levels. Before heading out of the factory, each converted Shelby GT500 is calibrated on the dyno before heading out to the road for real-world testing.

"The stock Shelby GT500 is an extraordinary muscle car, but we take it to the nth degree with our Venom 1200," says company CEO John Hennessey. "Our engineers were able to coax more than 400 additional horsepower out of the engine, which takes performance to supercar levels. Only a handful of vehicles in the world offer this level of power…especially at this price point."

Speaking of, the conversion kit costs $59,950 (you'd have to supply your own GT500, of course), but that amount of cash will guarantee a certain level of exclusivity, as just 66 examples (in reference to the GT40's Daytona triumph) of the Venom 1200 will be built. Optionally, owners can add the 1966 24 Hours of Daytona Ford Mark II GT40 livery to the car, with its red, white, and black color scheme, for $4,950.

As always, a warranty is included too, which in this case is active for one year or 12,000 miles.