It didn't take long for the public to acknowledge the performance of the Hemi engine, and Chrysler, recognizing a product hit with greater potential, started to spread Hemi engine design through the rest of its family of vehicles. In 1952, DeSoto offered a smaller, 276ci hemi V-8 called, appropriately enough, the FireDome. It produced just 160 hp, but it still enjoyed an advantage over most of the competitors in its price field. Dodge introduced the Red Ram Hemi in 1953 and made Hemi engines a staple of its truck line throughout the '50s. The only brand left out of the Hemi revolution that decade was Plymouth, which soldiered on with conventional inline six-cylinder and eight-cylinder engines-although Plymouth did offer a "poor man's" Hemi in the form of the poly-head V-8 in 1955 and 1956, a sort-of semi-hemi that was lighter and less costly to produce.
Despite its much-heralded reputation at the beginning of the '50s, there were no production Hemi engines available in Chrysler products by 1960. They ceased production in passenger cars after the 1957 model year, and Dodge trucks stopped offering them after 1959. The reasons why the Hemi disappeared after less than 10 years on the market were simple: complexity and cost. The Hemi was a complicated and costly engine to produce, while advances in combustion technology were making the simpler wedge-head engine more efficient.
The Street Hemi
Chrysler revisited the Hemi-head design in 1964, when it introduced a Hemi-style racing engine for the NASCAR circuit. It was an auspicious reintroduction of the engine design, as 426 Hemi-powered race cars finished First, Second, and Third at the '64 Daytona 500. Richard Petty won the race, after leading 184 of the 200 laps in his Plymouth-including lapping Second-place finisher Jimmy Pardue when the race was only half done.
Not surprisingly, the immediate and obliterating success of the new Chrysler Hemi racing engine caused a stir, particularly among those racers who didn't have one under the hood. After a few more races with similar results, NASCAR moved to restrict Chrysler's not-so-secret weapon by imposing a "production model" rule. This meant that, for the 426 Hemi to be legal in NASCAR competition, it had to be offered in meaningful quantity in regular-production street cars.
Chrysler was unprepared to offer the racing-only 426 Hemi in street cars. The company sat out the '65 season while it prepared to retaliate. They returned in 1966 with the all-new 426 Street Hemi and Chrysler quickly went racing again. There was little that was significantly different between the racing engine and the street version. The Street Hemi received two four-barrel carbs (the racing version had a single carburetor), lower compression, different valve timing, and iron cylinder heads. There were a few other minor differences, but the street versions were, for all intents and purposes, simply detuned versions of what Petty was using to run rings around the competition.
In 1966, the 426 Street Hemi was rated at 425 hp (gross) and 490 lb-ft of torque. It would remain in production through the 1971 model year, with its horsepower rating unchanged. Only a handful of changes were made to the Street Hemi during its production run, including upgrades in 1968 to reduce oil consumption and a change to a hydraulic camshaft and lifters in 1970.
Street Hemi-powered cars quickly became the stuff of legend and myth at small-town burger stands and urban street-racing venues. They developed a reputation for being unbeatable-when they were properly tuned. The fact was the twin-carbureted engine, with its high compression and high-rpm performance intentions, suffered when loped around at low speeds. The carbs loaded up and the plugs often fouled. The engine required constant attention and tuning, particularly the carburetors, but when all the dials lined up, the only thing that could catch a Street Hemi was another Hemi.