15 Muscle Cars That Were Built in Response to a Crisis — and Somehow Got Even Meaner

11. 1971 Plymouth Road Runner 440 Six Barrel

Confronted by rising insurance costs and new emissions restrictions, Plymouth refused to go quietly. The 1971 Road Runner 440 Six Barrel delivered uncompromising performance with its triple-carbureted 440-cubic-inch V8, representing one of the era’s fiercest muscle machines. This model was a bold, last stand for American high performance before regulations forced a retreat. Learn more about this brute’s legacy at Hemmings.