Chrysler A engine
The Chrysler A engine is a small-block V8 gasoline engine built by Chrysler with polyspherical combustion chambers. It was produced from 1956 until 1967, when it was replaced by the wedge-head LA engine. It is not related to the hemispherical-head Hemi engine of the same era.
Chevrolet big-block engine
The Big Block V-8 gasoline engine was used only in Chevrolet medium duty trucks and in school buses. It had a bore and a stroke of . This engine was made from the 1960s until the mid-1990s. The 366 used 4 rings on the pistons, as it was designed from the very beginning as a truck engine. The 366 was produced only as a tall-deck engine, with a deck taller than the 396, 402, and 454 short-deck Big Blocks.