Iskunpituus

Iskunpituus refers to the distance a piston travels within a cylinder from its uppermost point (Top Dead Center, TDC) to its lowermost point (Bottom Dead Center, BDC). This measurement is a fundamental parameter in the design and performance of internal combustion engines and other reciprocating machinery.

In an engine, the stroke length, along with the bore (the diameter of the cylinder), determines the engine's displacement. Displacement is the total volume swept by all the pistons in an engine during one complete cycle. A longer stroke generally results in a larger displacement, which can contribute to higher torque output, especially at lower engine speeds. Conversely, a shorter stroke can allow for higher engine speeds and potentially more horsepower.

The ratio of bore to stroke is often referred to as the engine's bore-stroke ratio. An engine with a bore larger than its stroke is considered "oversquare," while one with a stroke larger than its bore is "undersquare." These ratios influence an engine's characteristics, such as its responsiveness and its ability to rev.

Iskunpituus is a critical factor in engine tuning and modification. Changing the stroke length, often through modifications to the crankshaft, is a significant undertaking that impacts many other engine components and specifications. Understanding iskunpituus is essential for engineers and mechanics when designing, analyzing, or working on reciprocating engines.