Regal was first introduced in 1973 as a line extension of the popular Buick Century.
Originally, only a two-door hardtop model was available. Powered by a 350-cubic-inch two barrel V-8, its three-speed manual transmission was complimented by "AccuDrive . . . Buick's total roadability suspension system." Regal's curb weight of 3,996 lbs sat atop one of four available tire combinations -- each featuring whitewall tires.
Protective body side molding and door edge guards were available but not standard.
Buick produced 91,557 model 4AJ57 Regals in 1973, second most of any Buick model sold that year.
Source: The Buick -- A Complete History & Buick Motor Division