13. 1975 Plymouth Road Runner
In the ‘detuned era’ of the mid-1970s, the 1975 Plymouth Road Runner’s exhaust note stood as one of the few vestiges of its muscle heritage. Despite this, its performance was significantly reduced due to stringent emissions regulations. The base 318-cubic-inch V8 engine produced just 145 horsepower, while the more potent 400-cubic-inch V8 with a four-barrel carburetor and dual exhausts offered 235 horsepower. These figures were a far cry from the Road Runner’s earlier, more exhilarating performance. (hemmings.com)