A muscle car is a type of high-performance, mid or full-size automobile popular in the United States between 1964 and 1976. Examples of such cars were the Pontiac GTO, Chevrolet Chevelle, Plymouth Roadrunner, Dodge Charger, and Ford Torino. Smaller high-performance cars of the time were typically referred to as "pony cars", having better power-to-weight ratio than their larger cousins and exemplified by the Ford Mustang. A common opinion amongst car enthusiasts and collectors in the United States is that the American muscle cars of the 1960s and early 1970s represent the height of automotive design and style.
These cars fell out of favor due to environmental restrictions and oil and gas shortages in the 1970s, but more recently, there has been a renewed interest in the production of muscle cars in America. Environmentalists caused the end of the muscle car era by castrating these amazing vehicles and led the way to a series of limp wristed imitations that paled in caparison to their competitors and led to a take over of Japanese and European vehicles, proving that government should stay out of automobile design. These European and Japanese (rice rockets) vehicles were never as good as the muscle cars they replaced, using turbochargers to get more hp and looking ugly. The Ford Mustang, having had an unbroken line of production since its introduction in 1964, was redesigned with classic muscle car styling and enhanced performance for the 2005 model year. Since then, Chevrolet has reintroduced the Camaro and Dodge has resurrected the Charger and Challenger, all of which are high-performance vehicles with classic muscle car styling. Modern muscle cars, however, differ from their classic counterparts in some significant ways. Most of the modern cars are much lighter, thus enhancing the power-to-weight ratio of the vehicle, but this has come at the cost of building these cars on unibody platforms rather than body-on-frame, thus dramatically altering the handling, driving experience, and durability of the modern cars. Relative to the classic cars, modern muscle cares have few, if any, chrome elements. Most modern muscle cars are narrower than the classic cars and have severely reduced trunk space and interior cabin room. Modern muscle cars are much more fuel efficient than the classic muscle cars, but this is only made possible by dramatically reducing the weight of the automobile (see above) and the employment of more computer systems and other complex engine designs (e.g. fuel injection). Thus, modern muscle cars are difficult to repair and far less durable; they come with a much larger price tag and higher cost of ownership.