What does BDC refer to in piston strokes?

BDC refers to Bottom Dead Center, which is an important term in understanding the operation of internal combustion engines. In the context of piston strokes, Bottom Dead Center describes the position of the piston when it is at its lowest point in the cylinder. This position is critical because it represents the point where the volume of the combustion chamber is at its maximum, and the intake and exhaust events occur relative to this position.

Understanding BDC is essential for grasping how engines operate, particularly in terms of timing for valve operations and the overall cycle of intake, compression, power, and exhaust strokes. Knowing when the piston reaches BDC helps in determining when the air-fuel mixture enters the cylinder and when combustion occurs. This concept is foundational in engine mechanics, as the accurate synchronization of the piston movement with the opening and closing of valves directly influences engine performance and efficiency.