Electrolysis of water to produce HHO does not require hardly any actual amperage, it's a matter of voltage....12V being the start but then you can use step-up transformers to produce high voltage amounts to release more gas. You are not heating the water-you are separating its basic gasses, hydrogen and oxygen. Hydrogen is FAR more combustible than gasoline so small amounts go a long way and that enables you to reduce the supply of gasoline required to do the same amount of work. I am not an expert on this but I can tell you through voltage amplification, you can achieve what amounts to a 300-400% efficient engine vs. the roughly 20% efficiency todays engines currently exhibit. Remember all the talk a few years back about auto manufactures going to a 42V system? Funny how that was dropped and nobody is asking why, huh? Ford for some unknown reason has just dropped their research on water fuel systems (think of 80 mpg V8 Mustangs...wow!) that they privately held at a high regard...that stinks too.
The keys to using water as power is to first break up the fuel in your tank chemically, then you need heat the fuel below its vaporization rate of 212 degrees so 200-205 is where I would start. Then, using a well designed water fuel cell, capture the two gasses and have them enter the combustion chamber with the fuel-here's where fuel injection engine are easier to modify: since the hyrogen gas by itself is 6x more combustible than petrol, you can now lean the fuel out gradually. This is where a little hydrogen gas goes a long way. This is the most basic principles of water fuel but then you have to take into account what the engine's computer is trying to do. It wants to see a 14:1 stoichmetric air/fuel ratio so it will do whatever it has to do in order to keep what it sees as safe. This is where the O2 sensor if left unmodified will be a huge detriment to the water fuel system. Remember that we want to create combustion here-the computer nor the engine to a certain extent cares what type of fuel is used, only that it does so without huge cylinder pressures and detonation. Well, hydrogen has a very wide range of flammability so even @ high compression ratios of say 13:1, 14:1 the engine will not detonate. So how does the O2 sensor "read" the exhaust gasses? It does so through resistance values. And the O2 sensor(s) work in concert with the coolant temp sensor and the air charge temp sensor to determine not only timing but also fuel pressure and volume. So the trick here is to make the factory computer "see" what it wants to see while at the same time taking advantage of a water fuel system. You do this by hard wiring resistors into the computer inputs for that given sensor circuit. So now the computer will be happy, it will not make unwelcome changes as you lean out the fuel nor will it trip your OBDII check engine light. Now you can go further with resitance to the fuel injectors to reduce fuel requirements, etc. Even your vehicle warranty can't be voided because according to the Moss-Magnuson Act of 1996 any aftermarket device will not void your manufactures warranty unless it created damage or otherwise increased the inefficiency of the engine/drivetrain. Well, an increase of over 300% in fuel economy of being 99.9% emission-free certainly would not constitute an "inefficeincy" in anybodies eyes I wouldn't think. There is so much more to this that what I just mentioned buy hopefully you get the idea. And for the record, all water fuel kits are junk if they do not take into account any way of modifying a factory computer. The factory computer will revert to a preset fuel curve once the engine is either too out of tune (so you have time to correct the issue) or if you are achieving too much efficiency to the point where the A/F ratio appears too lean (water fuel cars can run safely at 40:1 A/F btw) as the computer sees it, that too will flag the default fuel map and throw up a check engine light. Weird how big government has gone through great strides to only guarantee a certain mpg through electronic engine management, huh? Imo 100 mpg designs have been on the drawing board and been proven for the last 50 years but big oil would have a lot to lose if water technology was turned loose for the public.