A modification package designed to increase the cubic inch displacement of a specific General Motors engine, the big-block Mark IV 454, is a frequent upgrade path. It involves replacing internal components, notably the crankshaft, with parts that have a longer stroke. This alteration increases the distance the pistons travel within the cylinders, resulting in a larger swept volume and, consequently, greater engine output. For example, a standard 454 cubic inch engine, when fitted with such a kit, might see its displacement increase to 496 or even 505 cubic inches.
The significance of increasing engine displacement lies in its ability to generate more torque and horsepower. Historically, this approach has been favored by enthusiasts seeking enhanced performance in various applications, from street vehicles to racing cars. The larger displacement translates to improved low-end responsiveness and increased overall power throughout the engine’s operating range. The availability of these packages has allowed for a cost-effective method of achieving substantial gains in engine performance without resorting to a complete engine swap.
