Yea, I know fukin' BMW, Audi or any Japs shit ain't musclecars but I have always considered Corvette as musclecar... Guess I have to reconsider then 
Corvettes are sports cars, after GIs came back from WWII they wanted the cars that they saw in England---Austin Healeys, etc. Small, light, two door, two passenger minimalist cars...great handling, etc.
GM came up with the Vette, Ford came up with the Thunderbird...
By 1958, Ford abandoned the the 2 seater model, for 4 seats, Corvette soldiered on, handling and performance were the "sportscar's" forte.
Musclecars had big engines in relatively lighter (but gradually bigger) bodies---straight line perfornance was above all the King.
Engine tech was far ahead of tire and suspension tech. Styling was flamboyant, color represented that with Nicknames (Grabber, Plum), trim levels (Road Runner, Boss, etc).