1970 Superbird
With the strict competition of the 1969 NASCAR Aero Warriors. It was the Dodge Charger Daytona against fastback Ford Torino's and Mercury Cyclone's. Plymouth would get its own version of this winged wonder in 1970. This model added upright spoilers for stability with a top spoiler for down force and an aero shaped pointed nose cone in front. It was also to lure Richard Petty back to Plymouth after defecting to Ford Motor Company in a Torino for a year. Because Petty he wanted a Plymouth winged car. While spectacular on the track, consumer response was luke-warm, leading some dealers to remove the wing and nose, making them appear more like normal Road Runners. In the 2000s, these would fetch among the highest prices of any muscle car at auctions.
Trying to capture some of the success that their Dodge brothers had in 1969 with the Charger Daytona. It was decided that the 1970 Super Bird would be made to get Richard Petty back from Ford. According to Road Test magazine, performance was around 0 to 60 mph (97 km/h) in 5.5 seconds, 1/4 mile in 14.3 seconds at 104 mph with the Hemi. Although similar in appearance, the Superbird was actually quite different from the Daytona. The Superbird was based on the Plymouth Road Runner and the nose, airfoil, and basic sheet metal was different between the Daytona and Superbird. The special nose added 19-inches (483 mm) to the overall length (the Daytona's was 18-inches or 457 mm), and the trunk spoiler was more angled and higher than the Daytonas. On both models, the spoiler was three feet high. Although it created quite an impression on the street, the wing was not needed at normal highway speeds; it was designed for speedways, to keep the rear wheels to the ground at 150 mph (240 km/h) and higher speeds.
NASCAR only required 500 copies to be built in 1969, but in 1970, NASCAR required a manufacturer to build one unit per dealer. In the end, Plymouth built a total of 1,920 Super Birds. Super Birds were available with three different engines. The most popular was the basic Super Commando 440 V8 with a single four barrel carburetor rated at 375 bhp (280 kW). Next up was the 440 Six Barrel rated at 390 bhp (291 kW). At the top, and ordered by just 93 buyers, was the mighty 426 Hemi, rated at 425 bhp (317 kW). Despite the success of the Super Bird on the tracks, 1970 would be the only year it was made.
The reason for using such a tall spoiler was so on the production version the trunk could open. In test the spoiler didn't need to be so tall. The tallest the spoiler had to be was the same height as the roof.
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