Harry Miller ranks among the most idiosyncratic, famed, and successful racing car constructors of all time.

His contributions to the design of American competition cars are legion, including developing the first aluminum pistons, but he is best-remembered for his all-conquering “Miller 91” of the late 1920s—which so dominated America’s speedways that the AAA literally changed the rules to the production-based “junk formula” to give others a chance.

The 91-cubic-inch, twin-cam eight-cylinder engine was supercharged to develop, in its initial form, 155 brake horsepower at 7,000 rpm, a figure that development soon raised to over 250 brake horsepower at 8,000 rpm—enormous figures for such a tiny jewel of an engine.

It ran on both rear- and front-wheel-drive chassis, the gorgeously low-slung latter a configuration also pioneered by Miller, and which would inspire the similar layout of the Cord L-29 production car.

On both it was renowned for its top-end speed, with Frank Lockhart achiev...