Dynamic Compression Calculator

Static compression tells you the geometry; dynamic compression tells you what the engine actually sees. Enter your static ratio, intake closing point and rod/stroke geometry to estimate real cylinder pressure.

🔧 Real-world math

Models the compression stroke starting only after the intake valve closes.

📈 Cranking psi

Estimates the pressure you would see on a compression tester.

⚡ Fuel matching

See whether your build is safe on pump gas or needs race fuel.

🔒 Private

All computed locally in your browser.

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