So how does running your 1300 watt amp affect your fuel economy? Do you get 20% less fuel economy or about the same as with it off? I doubt it makes a huge difference. I have no idea what my 6 channel JL audio amp pulls, but I notice no difference in power or economy with it on... I would imagine, and perhaps I am wrong, that one of the HHO systems wouldnt pull more current than the amp requires. So again, I dont see it as a huge draw on a HO alternator...
Again, I dont purport these things to work. As I have said before, I havent built one and am not totally sure how these are plumbed...but I have read a little. In some cases, unmetered air coming into the system may be generating a lean condition that helps with economy...maybe not the best idea as too lean can be very bad for the engine. If in fact these systems are "closed" to the engine, however, I am not sure how to explain some peoples successes...other than that there may be something to it...whio knows maybe they are steam-cleaning their engine and its literally combusting very dilute water vapor and not 'HHO'. As a researcher, I am a paid skeptic and at the same time asked to synthesize the perfect "needle for the haystack". While I am full of doubt until I can see and touch something, I think there are enough people out there who have built these types of devices who are not trying to sell or market you anything, many are just saying here it is, check it out, hence there may be something to it. I wont bag on it until I can see one "working" and check it out in person.
As far as putting one on one of our trucks, if its a cruiser, maybe, if its a wheeler, probably not, but you could always plumb in some valves or quick disconnects before you hit the trail to keep water and electrolytes out if you go rubber up.