Nitrous Fuel Enrichment Calculator
Liguori Drag Racing • Nitrous
Nitrous Fuel Enrichment Calculator
Estimate added and total fuel demand from engine power, nitrous power and your fuel-consumption assumptions.
Starting power and BSFC values are illustrative assumptions, not a nitrous tune. Use crankshaft horsepower for both power inputs. Actual enrichment must be established for the specific engine, fuel and nitrous system.
Results
Method and assumptions
Estimated defaults (engine / incremental nitrous, lb/hp/hr): gasoline 0.50 / 0.60; high-ethanol 0.70 / 0.80; methanol 1.10 / 1.30. These are editable planning assumptions. Fuel octane and density alone cannot establish actual BSFC. Custom fuels and intermediate ethanol blends require your own values.
Baseline fuel = engine horsepower × engine BSFC. Added fuel = nitrous horsepower × incremental nitrous BSFC. Enrichment % = added fuel ÷ baseline fuel × 100. Volume uses the selected fuel’s specific gravity and mass flow. BSFC means fuel mass consumed per horsepower per hour; fuel selection supplies generic fuel-type estimates, not measured BSFC for a particular branded fuel. Engine defaults assume naturally aspirated operation before nitrous. Incremental nitrous BSFC is an assumed added-fuel coefficient, not the combined engine BSFC. Manufacturer whole-engine nitrous BSFC ranges do not establish this incremental coefficient. Specialty oxygenated blends and boosted engines need application-specific values.