We may want to begin with the PWM for Electrolyzer Current controll. Which very soon would require to be based on throttle position measurement using a Slope/Timer Based ADC (GoBox/TargetSpecifications)
Deducting from my personal experience (Tobias) we would at this point also need to measure and replace the Oxygen Sensor Voltage with our own version (that is while there is still the cars own Carburation / Fuel Injection Control). This is so we can efectively make the mix leaner. As a result it will also become necessary to start with water injection to reduce the chance of knock.
In the long run we may hope to adjust the ignition timing based on Knock and IonSense Data. If all goes like I predict we will then not be able anymore o use a conventional Oxygen (lambda) sensor but need a heated sensor like specified in WideBand.
Fuel Injectors are the ideal method to administer the GoBox/HydroCarbons we will see if there is another method.
To create a Model that describes the System sufficiently we shall continue to describe the expected processes and extract Keywords for their Object and Parameter(variables) usefullness.