Dry Nitrous-to-Fuel Flow Ratio Calculator

Liguori Drag Racing • Nitrous

← All Calculators

Dry Nitrous-to-Fuel Flow Ratio Calculator

Compare nitrous flow with the extra fuel supplied through your injectors.

For dry nitrous systems. Enter the combined fuel flow of all injectors, first without nitrous and then with nitrous. The calculator subtracts the first value to find the added fuel.

Use measured or logged fuel mass flow in lb/hr, not injector size, pulse width, duty cycle or an ECU enrichment percentage. Compare matching engine speed and load conditions. If your ECU estimates fuel flow, this result is an estimate too.

Results

How this works

Nitrous flow = nitrous weight used ÷ test length. Added injector fuel flow = total fuel flow with nitrous − total fuel flow without nitrous. Nitrous-to-added-fuel ratio = nitrous mass flow ÷ added injector fuel mass flow, after converting both to the same units.

Example: 100 lb/hr without nitrous and 145 lb/hr with nitrous means 45 lb/hr of added injector fuel. This example is arithmetic only, not a tuning recommendation. The ratio is not engine air/fuel ratio or lambda and does not establish a safe tune. Baseline subtraction only represents nitrous enrichment when the compared operating conditions are suitable.

Check injector capacity with nitrous →