Engine Displacement and Compression Ratio

Cubic inches / liters and static CR from bore, stroke, chamber, gasket, deck, and dome volumes.

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Formula and source

Displacement (in³) = π × (bore/2)² × stroke × n_cyl. Static compression ratio CR = (V_swept_per_cyl + V_TDC) / V_TDC where V_TDC = chamber + gasket + deck − dome.

Classical engine-design geometry; SAE J604 displacement / SAE J1349 power-rating by name.

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