What years used the 8-6-4 engine?

The 8-6-4 engine, a notable feature of the Cadillac lineup, was used primarily in the Cadillac models from 1981 to 1983. This engine was part of an innovative approach to improve fuel efficiency by using a variable displacement system that allowed the engine to operate on fewer cylinders under certain conditions. The system was ultimately discontinued due to performance and reliability issues.