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Fuel inj general

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Injection method

Specifies injection mode.

Sequential is always preferable, but requires a fitted cam trigger sensor.

Simultaneous - All injectors are opened at the same time once every 720 degree.

Group - Injectors are opened every 360degrees, but only half of them

Sequential 360 - Injectors are opened individually on each cylinder every 360 degrees.

Sequential 720 - Injectors are opened individually on each cylinder once per engine revolution. If injection/ignition is in the wrong engine cycle, change Cam signal position in Inputs --> Trigger, Trigger decoder.

Sequential 720 without sync - Injects fuel every 2 crankshaft revolutions. Used with trigger systems without cam sync. As the ECU doesn't know if the cylinder is in the intake or exhaust cycle the fuel may be injected during either one. This is determined each time the engine is started, and will always be the same then engine is running.

Manual injection distribution (advanced) - See manual injection distribution, output entry method below.


Fuel stoich AFR

Specifies fuel type used on engine.


Multiply lambda

Specifies if lambda target values should be used for VE calculations.


Note: For MaxxECU to present "real" VE values, this must be checked.


Use MAP-sensor

Specifies if MAP sensor should be used for fuel calculations. <-- recommended.

Disable where TPS is selected as main load axis and MAP readings are unstable because of wild cams and/or intakes.

Note: Regardsless of your source axis values in ex the main VE table, the MAP-sensor value is used in the VE calculations when use map-sensor = enabled.


Staged injection

Enable/disable the use of staged injection functionality.




Specifies installed injector type.


Note: If your injector is missing, please use "Used defined" and enter correct values.


Injector flow

Specifies injector flow in cc/min at 3bar fuel pressure.


Fuel pressure

Fixed value - Specifies base fuel pressure. Used to adjust pre-defined injector flow based on a theoretical curve. 3 bar is a recommended value to use since this is default for most injectors when flow tested from manufacturer.

fuel pressure sensor 1/2 tracking - Use a fuel pressure sensor to be used for flow calculations. RealTime Data values are also visible which can be used in the warning system.


Injectors per output

Adjusts the injector drivers for the load.

MaxxECU PRO, RACE and V1 (rev7+) can use max 2 Peak-and-Hold injectors per output.

All MaxxECUs can use max 3 high resistance injectors per output.


Injectors per cylinder

Adjusts the fuel calculations to account for the fuel flow per cylinder.


Peak-Hold drivers

Peak and Hold drivers MUST be enabled for low impedance(below 8 ohms) injectors, and disabled with high impedance injectors (saturated).


Peak current

Specifies "peak" current which opens the injector.

3000mA = 3A which is default and used by most injectors.

Current above 5A per output is only allowed with 2 injectors per output.


Note: MaxxECU rev6+ and higher supports higher peak current, up to 8A.


Hold current

Specifies hold-current for injector.

1000mA = 1A works for most injectors.


Injector dead time

Injector dead time at different voltages. "Dead time" is the amount of time it takes for the injector to transition from closed to open.



Injection angle

Specifies the injection angle for each cylinder. Affects mostly idle and the low RPM band.



Output entry method

Output number - The output is simply the logical number of the output (as printed on the wire).

Outputs as bit fields - Bit field - Outputs are entered as bit field, so that several outputs can be triggered from ONE event.

Add the values for the outputs you want to trigger:

Ign1  = 1

Ign2  = 2

Ign3  = 4

Ign4  = 8

Ign5  = 16

Ign6  = 32

Ign7  = 64

Ign8  = 128

Ign9  = 256

Ign10 = 512

Ign11 = 1024

Ign12 = 2048

To trigger output 3 and 6, add the values for the outputs and enter the result 4+32 = 36



Fuel injection cycle

This is used to divide total fuel requirement on one or two injection(injectors?). This does not affect the actual injection, just the fuel amount calculation.

2 stroke engines should use 1.

4 stroke engines with 720 degrees injection distribution should use 1.

4 stroke engines with 360 degrees injection distribution should use 2.


Event output number

Event number is in the logical order 1-2-3-4-nnn and is not affected by the entered firing order.

The outputs entered needs to be adjusted for firing order.