High Quality Content by WIKIPEDIA articles! The Chevrolet big block is a series of large displacement V8 engines that were developed in the USA during the 1950s and 1960s. As American automobiles grew in size and weight following the Second World War the engines powering them had to keep pace. Chevrolet had introduced their popular small block V8 in 1955 but needed something larger to power their medium duty trucks and the heavier cars that were on the drawing board.