A modification package designed to increase the displacement of a marine engine, typically a small-block Chevrolet, to 383 cubic inches. This upgrade usually involves replacing the crankshaft, connecting rods, and pistons to achieve a longer piston stroke within the engine’s cylinders, thus increasing the total volume of the cylinders.
The implementation of such a package offers significant performance advantages for marine applications. The enhanced displacement results in greater torque, which is crucial for accelerating heavy boats and maintaining speed under load. Historically, engine builders and boat enthusiasts have sought increased displacement as a reliable method to improve power output and overall vessel performance without fundamentally altering the engine block’s design.