Chamber Volume for a Target Compression Ratio
The inverse of the displacement-cr tile: the combustion-chamber volume needed to hit a target static compression ratio, TDC_volume = cylinder_cc / (target_CR - 1) and chamber = TDC_volume - gasket - deck + dome. A 4.0 x 3.48 in cylinder (716.7 cc) targeting 10.73:1 needs a 64 cc chamber; drop the target and the chamber grows. Tells you how much to mill the head or how large a dished/domed piston to run for a target CR, instead of the CR from one chamber. Static CR only; cc'ing the actual chambers governs.
Formula and source
TDC_volume = cylinder_cc / (target_CR − 1); chamber_cc = TDC_volume − gasket − deck + dome. The inverse of CR = (cylinder_cc + TDC_volume) / TDC_volume. 1 in³ = 16.387 cc.
Classical engine-design geometry; SAE J604 displacement by name.
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