The Duster was a success for Plymouth, so much so that in 1971 Dodge requested and received a version, the Demon. In response, Plymouth was given a version of the Dodge Dart Swinger 2-door hardtop named the Plymouth Scamp.
The Plymouth Duster introduced in 1970 was all Valiant from the cowl forward, but the rest of the car's sheet metal, save door skins, was completely different. The design incorporated a semi-fastback roof and a special rear valance with twin horizontal taillights, unusual for having no bezels.
When all was said and done in 1974, the Barracuda had by far its worst sales year ever, and production was only 11,734, which also represented the lowest production number for any pony car.
In 1973 the Muscle Car world was fading, and that year’s Arab oil embargo didn’t help. The 73 Model was almost an exact clone of the 72 except for the use of 5 MPH bumper reinforcements on front and rear.
As the ‘72’s hit the streets, both emissions and safety were grabbing government (and insurance company) attention. In response, the big-block was gone from the ‘Cuda’s option sheet.