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2026. 6. 30. 작업

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What does under-square and over-square mean?

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You Asked What do these terms mean? These terms are related to the bore and stroke measurements of a pistons travel inside a bore of an internal combustion engine. Bore is the diameter of the cylinder. Stroke is the distance a piston travels within a bore. What does under-square and over-square mean? Under-square refers to a piston diameter measurement that is smaller than the stroke length measurement. Over-square refers to the opposite. A stroke length measurement that is smaller than a piston diameter measurement. How do they apply to engine building? They are essential components to accomplishing a particular goal in engine building. A larger bore allows a larger piston. A larger piston allows for a larger combustion chamber. A larger combustion chamber allows for larger valves which will effect the quantity of gasses that can potentially flow through the ICE. In pushrod engines a longer bore can create more valve reciprocating weight due to the longer pushrods. In DOHC engines a s