I'm running parallel plates; as many as I can fit into a 3" pvc pipe. I mount the tubes horizontally so that the bubbles do not "back up" on the plates and cause etching and heat. My spacing is wider than what I read posted here. I add KOH until the conductivity is minimum, then add some more so I don't have to mess with it for a while. I divide the voltage before the cell so that the voltage applied to the cells is approx. 3-4vdc. Current is generally around 15-20 amps depending on the build. Since it is a series circuit, and current is what produces HHO, the max current is applied to all components by design. I have no over-heating issues or thermal runaway. Actually, I have a lack-o-heat issue. Using an inline rotometer style flow gage(biased for HHO per the supplier), my LPM is approx. .8. My engine tuning/mods are simple: Efie's on all O2 sensors, Diode in series with MAP sensor supply voltage (drop .7 v), toggle switch controlled air and water sensor bias resistors. Toggle eliminated cold starts. I am saving money on gas. Mission accomplished.
Randohr
02' Jeep; 18mpg Highway w/o HHO
23mpg highway w/ HHO.
Parallel plate water baths, 3vdc, 16A
Efies(x4), MAP diode, AIT mod, WTS mod.