Developed specifically for NASCAR racing, the Superbird, a modified Road Runner, was Plymouth’s follow-on design to the Charger Daytona fielded by sister company Dodge in the previous season.
“Superbird” decals were placed on the outside edges of the spoiler vertical struts featuring a picture of the Road Runner cartoon character holding a racing helmet. A smaller version of the decal appears on the driver’s side headlight door. Superbirds had three engine options: the 426 Hemi V8 engine producing 425 hp (317 kW), the 440 Super Commando Six Barrel with three two-barrel carburetors producing 390 hp (290 kW) and the 375 hp (280 kW) 440 Super Commando with a single 4-barrel carburetor. Only 135 models were fitted with the 426 Hemi.