The 427 Shelby Cobras had it all: looks, power, sound.
As far as mass-produced cars the 1970 Chevelle SS with the LS-6 454 was the most powerful.
There are other genre’s of “muscle” cars that get overlooked because they are luxury barges, but they had some serious engines in Lincolns and Cadillacs during this time frame. 460s, 472s, and of course the 500 CID Cadillac. They weren’t drag strip screamers, but they produced mountains of torque.
My dad bought a new Eldorado in 1970. 500ci and 425hp sitting on top of that front wheel drive.
Red light to red light it held it’s own against them all.
Have to go with with ‘70 Chevelle. Only because I owned one and it was a great car.