The Clifford Performance company manufactures parts and accessories to increase the performance of six-cylinder engines to match the performance of larger V-8 engines.
Clifford Performance was established as Clifford Research by aerospace engineer Jack Clifford in 1967. Jack Clifford began developing automobile parts because of his interest in drag racing during the 1950s, which he used to increase the performance of a 1954 Hudson Flathead 6 engine.
To increase the performance of six-cylinder engines produced in the U.S. in the 1960s, Clifford designed modified parts for the intake and exhaust systems, including an exhaust header and intake manifold. These modifications gave six-cylinder engines a similar performance to the larger, more powerful V-8 engines.
Clifford Performance is headquartered in Wildomar, California, where the company manufactures exhaust headers, cams and intake manifolds. Exhaust headers produced by Clifford Performance are created using 16 gauge tubing.
