John Hennessey is an American entrepreneur and automotive engineer best known for founding Hennessey Performance Engineering, a company that specializes in high-performance vehicle modifications. Established in 1991, the company gained fame for its work on various sports cars, including the Chevrolet Corvette and Ford Mustang, enhancing their speed and power. Hennessey is also recognized for creating the Hennessey Venom GT, a supercar that set records for speed. His passion for performance vehicles has made him a prominent figure in the automotive industry, where he continues to innovate and push the limits of car performance.