On February 14, 42.9 seconds after he put his foot to the pedal of the Hennessey Venom GT, professional test driver Brian Smith experienced a first: The car hit 270.49 mph, besting the Bugatti Veyron's 269.86-mph mark, set in 2010, for the highest speed reached by a production car. "It was like driving into uncharted territory," says Smith. "I was traveling the length of one and a half football fields per second."

Created by a Texas aftermarket modification outfit, Hennessey Performance, the hand-assembled Venom GT is the shell of a Lotus Elise stuffed with a Corvette-style seven-liter GM LS twin-turbo V-8, then bolstered by all-carbon bodywork. The six-speed supercar – which has a limited run of 29 models and costs $1.2 million – weighs 2,743 pounds, churns out 1,244 horsepower, and rockets from 0 to 60 mph in 2.7 seconds.

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Founder John Hennessey came up with the idea in 2007, after his Dodge Viper-based Venom hit 200 mph in 20.3 seconds (also a record). That feat made him wonder whether he could put a V-8 in an even lighter frame, like the Lotus'. It took three years for Hennessey's 12-man team to take the idea from paper to pavement, plus two years of testing to ensure the Franken-car could sustain speeds near 300 mph. "We're just a little company from Texas with a passion for speed and performance," Hennessey says. "That we can build a car made in America and say it's the world's fastest is an incredible thing."