A muscle car refers to a high-performance car with a V-8 engine that is mid-sized and affordable, according to Muscle Car Club. Early high-performance full-size cars, as well as some compact and pony cars, also qualify as muscle cars under certain criteria.
One example of a muscle car is the Dodge Charger. Only R/T versions of the Charger are muscle cars by Muscle Car Club's definition. The Mercury Cougar is a pony muscle car if the vehicle is a GT or an Eliminator or has a Boss engine. Pontiac Firebirds are only muscle cars if they have engines with at least 400 cubic inches of displacement. The Pontiac GTO is the first true muscle car.