[MethoD]

I would like to connect my HFS-4 to my Link G4+ ECU in such a way that I can control the signal (and flow) of the water/meth injection independent from the fuel injector DC.

The Link ECU has general purpose Aux outputs that can deliver a PWM signal with variable duty cycle. I can assign the DC based on a 3D table with RPM and MAP as X and Y axis.

What I am not sure of is how to wire the HFS to the Link ECU.

The HFS has wires for both "conventional" injectors and "peak and hold" injectors. I don't know which set of wires to connect to the ECU.

Also, I am unsure of how to connect the wires to the ECU. Would the (+) go to a switched 12v from the ECU and the (-) go to the Aux? Or would the (-) go to ground and the (+) go to the Aux output? I think the Aux can be configured for either type of switching.

Thanks in advance
MethOD