Because the what is usually accepted as the first muscle car, the 1964 Pontiac GTO, was a mid-sized, 1964-'72 American car with a big V-8.
Don't be silly. The original muscle cars were mid-sized American cars of which there were different variations later on from Canada and Australia.Justify to us why is this original-type vehicle (below) should not be considered a Muscle Car?
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