The Chrysler A engine is an OHV small-block V8 gasoline engine built by Chrysler from 1956 until 1967. It featured polyspherical combustion chambers, and was offered in displacements from 276.1 cu in (4.5 L) to 325.2 cu in (5.3 L), and in various high-power configurations. It began to be replaced by the wedge-head LA engine in 1964, and is not related to the hemispherical-head Hemi engine of the 1950s or 1960s. The A engine was released in 1956, and was used exclusively in Plymouths until 1958 and in Chryslers and Dodges from 1959 on. The DeSoto and Dodge 270/315/325 poly used similar head architecture but was not related to the Plymouth A Engine, using its own heads and the same bottom end as the Dodge and Desoto Red Ram Hemi. The A engine cylinder bore center distance is 4.46 in (113.3 mm), larger than the earlier Dodge-based poly engines. The A engine formed the design basis of the Chrysler LA engine, evidenced in the many parts that interchange between the two engine families.