The Aero Wars: It was a period in stock car racing when Chrysler pulled out all the stops to "win on Sunday." Aero warriors came about because of the competition between Chrysler and Ford at tracks across the nation. When it came to engines, the Hemi was going to be a dominant force, (and we know what happened next). the factory and car owners had already employed just about every idea they could think of to gain the most horsepower from them. So they began to explore alternative methods of getting speed out of their automobiles. Aerodynamics became the next frontier to be challenged.
The factory's focus on aerodynamics can be seen in production cars like the Daytona or this Superbird owned by William Graul of Sinking Springs, Pennsylvania. Sure, the Superbird was limited in its number of production, but met the required production figures to be included in NASCAR. In an excerpt from a telegram to Chrysler from the Automobile Competition Committee we read, "Completion of dealer survey by ACCUSFIA covering the Plymouth Superbird indicates that Chrysler/Plymouth has complied with the production requirements established for 1970 stock car racing. The Plymouth Superbird as delivered to dealers is therefore eligible for competition as of this date."
The Superbird began life as a conglomeration of existing Plymouth parts and pieces specific to the Superbird. Actually, the body was from the Road Runner, and the front fenders and hood were confiscated from a '70 Coronet and modified to make the Superbird. The front fender scoops mounted on the fenders were made of injected plastic, and there were two distinct shapes to the scoops-a flat type on the Daytona and a rounded one on the Superbird. Chrysler contends the scoops were needed to gain tire clearance because the nose created enough down force when high-speed cornering that the tire rubbed the fender. According to Chrysler reps, all racing Superbirds had holes cut in the fenders underneath the scoops, while retail sale Superbirds had the scoops but no holes cut in the fenders. The reasoning behind the deletion of the holes in the street version was that Chrysler realized the leniency of the Homologation Rule. When the '69 Daytona was released for NASCAR's inspection, the holes in the street cars were cut the same as its race bred brethren. realizing there was some leniency towards the "exactly like" interpretation in 1970, Chrysler saved time and money by not cutting holes in the Superbird fenders. When it came to the rear window, a more rounded style was needed around the rear of the roofline. For this, a rear plug was fabricated, creating a smaller window opening; hence the rear window was scaled down. Since the Road Runner body needed a plug installed to resize the backlite, all Superbirds came with vinyl roofs.
In addition to the huge wing mounted to the rear of the car, the most noticeable deviation from the Road Runner body was the nose. The nose itself was made of steel, and the vacuum-controlled headlight buckets were made of fiberglass. The aluminum wing on the rear of the car featured a pitch-adjustable crossbeam. the wing and the nose were painted with a lacquer-based paint, while the body was painted with an enamel base paint. Even though it is well known Creative Industries was responsible for the conversions, it is not as well known the painting of the added components was not handled at CI. When the conversions were done, the cars and their parts were shipped back to the Chrysler Training Center to be painted.
The available engines for the Superbird consisted of a U-code, single four-barrel 440, a V-code Six Barrel 440, and the R-code Hemi engine with twin carbs. You could opt for either the A-727 auto or the A833 four-speed manual. The rearend choices featured either the Performance Axle Package (831/44) or the Trak Pak with a Dana 60. Rearend choices were influenced by transmission choice.