Route 66 Plymouth Neon Sign: Featuring Hemi 426 Roadrunner – NS6450

History Of The Hemi 426 "Elephant Engine"

Of the great American Muscle Car Engines of the 1960’s, the 426 Hemi is perhaps that most famous of all. From dominating the racing circuits across the country; including everything from NASCAR to NHRA Drag Racing; to setting the World Land Speed records at the Bonneville Salt Flats, the 428 Hemi Engine continues to power that fastest vehicles in the world, even today!

The 428 Hemi, also known as “elephant engine" due to its large size and weight, and high power. It was the 2nd generation of Hemi (so named due to its hemispherical shaped heads) that was produced by Chrysler. Its nearly 11 inch deck height, and nearly 5 inch bore spacing, made it the biggest in racing at the time. It is rated by Chrysler as producing 425 horsepower, but independent testing has shown it to be in fact underrated, commonly producing up to 480 horsepower. It was produced between 1964 and 1971, but is still popular today, especially in auto racing circuits such as NHRA. The engine’s large spacing makes it an ideal engine to modify because there is plenty of room to work with, and due to its popularity, parts are easier to find than for other types of engines. In fact, the NHRA’s, Top Fuel and Funny Cars are built almost exclusively with this type of engine.

First publicly debuted at the 1964 Daytona 500, the cars powered with a 428 Hemi dominated every event during the week. This included the 100 mile duels, qualifying (Paul Goldsmith winning the pole), and concluded with Richard Petty winning that year’s Daytona 500 (with Hemi’s also placing 2nd and 3rd) in his Hemi powered 43 car. In fact, the Semi’s were so dominant that year, that the engine was banned from the event (and all NASCAR races) in 1965, partly due to it not having yet been made publicly available in production cars. It would be reintroduced in 1965 (only at short track events) where it again dominated, after Dodge partially satisfied NASCAR by making the engine publicly available in its Dodge Dart, and Plymouth Coronet. By 1966 they would fully be reintroduced into NASCAR after the release of the “Street Hemi”. It would eventually become the dominant engine in the sport throughout the rest of the decade. The Semi 428 was the power plant behind a majority of Richard Petty’s all-time record 200 wins, including his record breaking 1968 season.

The impact that the 248 Hemi Engine has had on the evolution of motor racing almost cannot be overstated. Both the design that would become known as a “Funny Car”, and the “rear engine dragster” were originally designed based on modifications to a Hemi 428 engine. In the streets, the engine ruled the highways of the late 1960’s, as it was installed in some of the most famous muscle cars of all-time, including all Dodge Chargers of that era, and the famous 1968 Plymouth Roadrunner, which is highly sought after by collectors, and incredibly rare. To top it all off, modified versions of the engine still hold the World Land Speed Records for non-jet/rocket powered vehicles, with speeds exceeding a maximum of 459 miles per hour.

Sources: Motortrend, Wikipedia