I am new here, in fact this is the first post so I am not going to be alarmed at the flames I get on this but here goes.
First off, most people that have tried one of the HHO units simply did not experiment enough to come up with good results or their expectations were sky-high and what little improvement that they received in mpg (if they even measured it correctly) was not enough for them to build upon.
Second, I don't sell the units and I don't make money off of it other than what I save in gasoline not purchased.
Third, I am not going to try and argue with the scientific sticky, I am sure those measured results are correct.
I am getting to work on my '85 with the 2.3 EFI/5 speed trans. I bought this truck almost 3 years ago for my son, who decided it wasn't his style so I took it back. For the last 2 years it has sat in the backyard collecting cobwebs and pine needles. Last weekend, I got it moving again and it now is sitting in my garage up on stands. First order of work is a complete clutch replacement, then to figure out the cold start/idle issue. Some brake work is needed along with replacement of fluids. Already replaced the radiator last weekend along with coolant due to previous overheating issue. So I am looking forward to picking the brains around here and getting my little truck ready for it's new life as a toad behind my RV.
Now back to the HHO stuff, which I am also going to put on the truck once I have the engine running as sound as possible. Just over two years ago my new 32 foot RV was getting an average of 7.2 -7.4 miles measured with a scan gauge tool. Using a 2-quart HHO unit, some minor changes to the ego sensors and some experimenting with mix ratios, I was able to get my mileage up to 11.4 at it's best. Normal mileage runs about 10.6 - 10.8 and I really happy with that for the cost and work involved. Now I am not going to tell you how to do this as there is way too much information available that you can research and figure out yourself. The few people that I have spoken to about it never try it but are usually quick to call it a hoax. The deal is you're not trying to replace all of the gasoline that you use, you just use the hydrogen as an additional fuel added to the current air/fuel mix, therefore cutting down some on the gasoline that you need to burn. Are the units fool-proof? Nope not at all, you have to use some common sense with them, it can be dangerous stuff, you have to keep them relatively clean and in long term freeze conditions, it's easier to just disconnect them. And is it plug and play - hardly, but it does work and the results are going to be different depending on a lot of factors. If you want to work on it and I do mean work on it, you can get some decent results, but if you expect to just throw a unit on your vehicle, add a mix of water and soda and expect 50%+ fuel economy increases, you're kidding yourself. It's not going to happen.