Chevrolet introduced its big-block V8 in 1965. Initially, displacements were around 396 and 409 cubic inches. Through several iterations and bore and stroke modifications, Chevrolet eventually reached 454 cubic inches (7.4 liters) in 1970. This larger displacement was achieved by increasing the bore and stroke of the existing big-block design.
So, while there wasn't a single "origin" point for the 454, its roots are firmly planted in the evolutionary development of Chevrolet's big-block V8 engine family starting in the mid-1960s.
