Nitrous Control

Many of the EFI Technology ECU products are capable of Nitrous Control. The most advanced features are found on XTR and R8 ECU products. These ECU's can control up to 8 independent Nitrous solenoids each with fully programmable timers.

The Nitrous Control is armed when the engine is above the rpm and throttle limits and is activated by the clutch switch. Some systems also use a master enable switch. After launch the ECU controls the Nitrous solenoids and Fuel Injectors to add fuel based on the flow and timer settings for each stage. The ignition timing is also retarded by the number of degrees programmed for each stage.

Nitrous Constants

Nitrous Configuration - Enables the different options available for the Nitrous control.
Nitrous RPM Enable - Sets the engine rpm at which the Nitrous control is active.
Throttle Limit - Sets the throttle angle at which the Nitrous control is active.
Injector Static Flow - Sets the static flow rate for the fuel injectors used.
Nitrous Disable RPM - Sets the rpm at which when above turns the the Nitrous off.
Target Bottle Pressure - Sets the target bottle pressure for the "Auto Purge" function.
Fuel Reset Delay - Sets the fuel reset delay time after the nitrous system is shut off.
Spark Reset Delay - Sets the spark reset delay time after the nitrous system is shut off.
Master Nitrous Disable - Sets the time that the nitrous solenoids are shut off.
Master Fuel Disable - Sets the time that the added nitrous fuel is shut off.
Master Spark Retard Disable - Sets the time that the spark retard is disabled.

Stage Tuning

For each of the 8 stages the user can program the settings for the Nitrous timers, Added Fuel and Spark Retard. Open the Stage 1 Constants and enter values for the following parameters.

Fuel Added (lb/hr) - The amount of total fuel to add for this stage.
NOS enable (secs) - The time after launch to activate this stage.
Fuel enable (secs) - The time after launch to add the fuel for this stage.
Spark Retard (degs) - The amount of spark timing to retard for this stage.
Shutoff (secs) - Sets the shutoff time in secs for this stage.

The added fuel for each stage is calculated by taking the ratio of the fuel added to the injector static flow rate. This is then divided by the engine rpm and converted to a pulse width that is added to the base value in the fuel map. The amount of total fuel to add is dictated by the size of the Nitrous solenoids and the customers required air/fuel ratio.

For optimum performance it is recommended that the engine has been well mapped for both fuel and ignition in the naturally aspirated configuration before activating the Nitrous controls. Any unused stages should have the fuel and spark parameters set to zero.

Notes

After launch the clutch switch is masked to prevent a reset due to engine vibration.
The master enable switch can only be reset if the throttle is below 75 deg.
Final Spark timing cannot be less than the static crank pickup position.

Winning Edge Electronics