From Chrysler press: Chrysler production car design was revived with the sleek, sculptured Forward Look designs of 1955 that transformed the product line overnight. The Forward Look flagship was the 1955 Chrysler 300, a striking automobile that combined smooth styling with brawny HEMI power.
The 300, arguably the first muscle car, became a legend on and off the race track and set records throughout the 1950s, including a 143-mph performance at Daytona Beach. Each year's model used a new letter of the alphabet as a suffix (skipping "i"), reaching 300L by 1965, after which the model was dropped.
As the Fifties progressed, Chrysler products began to sprout distinctive tailfins, ostensibly to improve handling and stability above 70 miles per hour.
The 1957 Chrysler brand standard-bearer, the 300C, was equipped with a standard 392-cubic-inch, 375-horsepower HEMI, two four-barrel carburetors, a high-output camshaft, Torsion-Aire suspension and the new Torqueflite transmission, making it the fastest, most powerful production car built in America that year and earning it the appellation “beautiful brute.”
Throughout the postwar years, Chrysler engineering leadership paced new styling advances. The company's engineering "firsts" from that era include the first "safety cushion dashboard,” the famous Chrysler push-button transmission (which became an icon of the '50s), power steering, torsion-bar suspension and the first practical alternator (introduced in 1960, it proved so successful it became standard equipment just one year later).