Veteran hot rod historian Tony Thacker looks at the history of hot rodding through the eyes of speed equipment manufacturers. The book begins with the early 4-cylinder engines.

In 1932, Henry Ford introduced the flathead V-8, which was slow to be adopted as the engine of choice in racing until the parts industry caught up. Once it did, the flathead, although interrupted by the war, was the engine to run until the automobile manufacturers introduced overhead-valve V-8 engines in the late 1940s. Chrysler’s early-1950s Hemi and Chevrolet’s small-block V-8 in 1955 spelled the end for the flattie. Both mills dominated well into the 1970s, and the speed industry was there to support all platforms in spades. During that period, every auto manufacturer made a V-8 worthy of modification, and the speed industry boomed. Eventually, the speed equipment manufacturers grew to the point of becoming corporate entities, as mergers and acquisitions became the much less interesting story.