The Chevrolet brothers’ OHV head gave Ford’s Lizzie new legs – David Conwill @Hemmings

The Chevrolet brothers’ OHV head gave Ford’s Lizzie new legs – David Conwill @Hemmings


Even in its stock form, the Ford Model T was a decent performer for its era. Charlotte’s Web author E.B. White recalled in 1936, “Its most remarkable quality was its rate of acceleration. In its palmy days the Model T could take off faster than anything on the road.”

One of the best ways to go even quicker in a Model T has always been to swap out the flat cylinder head for an aftermarket job utilizing overhead valves—actuated either by push rods or overhead cams. The engine on these pages—part of a genuine pre-World War II gow job in the collection of Lang’s Old Car Parts in Baldwinville, Massachusetts— features the venerable Frontenac T (for “Touring”) overhead-valve head.

Frontenac was a creation of the Chevrolet brothers. Initially, the Frontenac name was associated with the brothers’ race cars, but much like Enzo Ferrari a generation later, Louis Chevrolet had ambitions of turning his prewar Frontenac race team into a producer of road-going automobiles.

Unfortunately, the road-car program was a victim of the postwar recession of 1920-’21 and Frontenac retired from the business of building automobiles before it started. The economy at-large was in crisis, and the brothers were looking for quick cash. With more than half of all cars on the road being Ford Model Ts and the proportion of low-budget racing cars being closer to 99 percent, they recognized an opportunity.

The brothers enlisted C.W. Van Ranst, chief engineer of their road-car effort, to design an overhead-valve conversion for the Ford engine. Van Ranst created a cylinder head that was both powerful and durable. Coupled with the brothers’ reputation, the Frontenac head was a winning formula.

The “Fronty” was hardly the first overhead- valve conversion for Fords, nor was it necessarily the most powerful, but it was the most successful, with around 10,000 of all types sold. The original Fronty head featured a single intake port and triple exhaust ports arranged in a crossflow design. It came in three varieties (Racing, Speedster, and Touring/Truck) and all three used the same 1:1.5 rocker-arm ratio to actuate two 17/8-inch valves per cylinder.

The addition of a Fronty T to a standard Ford automobile would increase horsepower from 20 to 33. They proved a popular addition to many mostly stock cars and trucks, and drove the bulk of production. As you may have guessed, however, our feature engine is not “mostly stock.”

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