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
The "LFA" is a Generation IV small block V8 truck engine. The "LFA" variant is used in the GM's "two mode" hybrid GMT900 trucks and SUVs, and is an all-aluminum design. It has a 10.8:1 compression ratio and produces at 5100 rpm and at 4100 rpm. Engine VIN code of 5.