I know you hate math Hornet, but here goes anyway.
I’ve gone through these numbers several times now, and they say this:
From this thread, I think I have found that your hydrogen generator produces 2 liters per minute.
I will assume it is at a pressure of say 20 psi absolute pressure. 5.3 psia over atmospheric. If this pressure is too high, the bottom line number in this post is too low.
The stoichiometric mixture of gasses you produce is by MW, 1:8 Hydrogen to Oxygen.
MW of H2 is 2.016 and O2 is 16.
So by the method of partial pressure, hydrogen is 2.23 psi, and the O2 is the rest.
From the perfect gas law, you produce 0.003331 lbm / hr of hydrogen.
From the JPL reports, from catalytic stripping of fuel, not splitting of water, they produced Hydrogen output flow rates of 0.4 to 2.1 lbm /hr.
This is 120 to 630 times your hydrogen output.
JPL brake specific fuel consumption (including the losses associated with the gas generator) decreases of 6 - 15% from the stock engine were observed over most of the engine BMEP - RPM operating- regime.
Your 11 to 16 mpg is a 45% increase in efficiency.
JPL achieved 6 to 15% with 120 to 630 times the hydrogen production, and produced it in a more energy efficient manner.
JPL produced 1/3 your improvement with 120 to 630 times the effort.