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 small-block engine
The Chevrolet small-block engine is a series of V8 automobile engines used in normal production by the Chevrolet Division of General Motors between 1955 and 2003, using the same basic engine block. Referred to as a "small block" for its comparative size relative to the physically much larger Chevrolet big-block engines, the family spanned from to in displacement.