What displacement did Chevrolet’s Mark IV big-block V8 have when introduced in 1965?

Chevrolet’s Mark IV big-block V8 had a 396-cubic-inch displacement when introduced in 1965.

The engine was developed as a new high-performance V8 family and initially appeared in Chevrolet passenger cars, including the Chevelle and full-size models. Its 396-cubic-inch size was created by combining a 4.094-inch bore with a 3.760-inch stroke.

The Mark IV family is often associated with Chevrolet’s later 427- and 454-cubic-inch engines, but those were separate displacements introduced after the original 396. The 409-cubic-inch W engine was an earlier Chevrolet big-block design, while the 454 became especially famous in the 1970s.

Chevrolet also marketed versions of the 396 under the Turbo-Jet name. Its combination of large displacement and strong torque helped establish the engine as a major part of Chevrolet’s muscle-car era.