Calculate engine compression ratio for performance tuning and optimization. Determine fuel requirements, analyze cylinder volumes, and find the perfect balance for your build.
Compression ratio is the ratio of the cylinder's volume when the piston is at bottom dead center (BDC) to the volume when at top dead center (TDC). It directly affects engine power, efficiency, and fuel requirements. Higher ratios increase power but require higher octane fuel.
Static compression ratio and boost pressure combine to create effective compression. Lower static compression (8-9:1) allows for more boost without detonation. Higher compression (11-13:1) provides better naturally aspirated performance but limits boost potential.
Pro Tip: For forced induction, start with 8.5-9.0:1 static compression. For naturally aspirated street engines, 10.5-11.0:1 offers the best balance of power and pump gas compatibility. Always leave 0.040" minimum piston-to-valve clearance.