I used the Faraday formula in the link you provided and
made a program that can be used to get results from different
combinations of pressure , vacuum , volts , watts , temperature
and according to my results so far it seems that every time
I use a pressure below 1 atm the amount of HHO generated increases.

at a 15 inch Hg there is a great increase.
and at a 26 inch Hg even greater for instance.
and this increase does not require any additional energy.

I think this program will assist in my HHO generator design.
so once again , thanks.

3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.