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.
LS based GM small-block engine
All Gen V engines are aluminum blocks with aluminum cylinder heads and include features such as direct injection, piston cooling jets, active fuel management, variable displacement oil pump, continuously variable valve timing and aluminum cylinder heads and block. However, it does retain its ancestors' two-valve pushrod valvetrain.