Aug 02, 2004 · High Performance Options for the 351M/400 Engine. From 1977 to 1982, M-block (351M/400) engines were a mainstay of Ford light truck powerplants. During this period, the M-block 400 was the largest V8 available from the factory in a 4×4 truck (Bronco or pickup). The 460 was not a factory option in 4×4 pickups until 1983.