Plymouth Duster 340 (1970)
As an economy brand, Plymouth was very active and successful at the lower end of the market since the early ’60s and the Valiant model. By the late ’60s and early ’70s, the compact market had grown, and Plymouth introduced the Duster 340. This model was a junior muscle car since it looked like bigger competitors but it had a more petite 340 hp engine rated at 275 hp (via Hemmings).
Plymouth never anticipated the success that the Duster 340 achieved and production doubled in just a few months. Despite being a compact model, the 340 was a very good muscle car. Its 275 hp moved the light body to respectable 0 to 60 mph times of just over six seconds. The vehicle may be half the size of some of the heavy hitters of the era but was almost as fast. Also, it cost just under $3000, which was highly affordable. Interestingly, after the original muscle car era ended in 1974, Plymouth continued to offer the Duster 340 but with the 360 engine option and less power due to rising emissions standards.