Ford introduced the 239ci Y-block in 1954 in Fords, and a 256ci version in Mercurys to replace its flathead V-8 introduced in 1932. The Y-Block swiftly grew to 272, 292, and finally 312 ci by 1956.

Another surefire way to identify a Y-Block is that the distributor is located at the rear of the engine instead of Ford's typical placement at the front. To be sure, the Y-Block wasn't all bad.