HHO kits, anyone used one

[LI0NSFAN]

We just recently got a new to us GMC Envoy XL, I love this thing!  The only thing that I don't like is that I can't get to family on one tank any more. I was interested in the HHO systems for several years now but having cars that get 30-40mpg I saw no need. I am not looking at the HHO to save money as much as I am looking at the miles per tank. We take 3-4 long trips a year and I would like to get there on one tank if possible. I was just wondering if anyone has actually used these systems themselves. I have plenty of "my cousins uncles brother has one" opinion so I have all those I need. I am looking for someone that has one in their personal car. It would be great if I could actually see one installed. Thanks in advance.

[Sam1]

Other than some internet stories, I haven't seen one of these kits in use.  The problem that you will have is anything with a computer on it will have to be completely reprogrammed because the hho will lean out the a/f, and the computer will compensate for that by dumping more gas in the motor (even though it doesn't need it).

 

Not sure what kind of options there are for chips, but it may end up costing you enough that it would take years to negate the expense of the hho system + you have to add in the hassle of actually having it on and maintaining it.

 

From what I have read (used to be interested in this stuff), here's a calculation by someone smarter than me:

 

Gasoline has around 44 MegaJoules/kg
H2 has around 121 MJ/kg

So, H2 has 2.75x the energy per weight of gasoline

So, if you assume 20 mpg now @ 60 mph, you burn 3 gallons per hr, which is 0.05 gal/min. Gas is about 4 kgs/gal so you burn 0.2 kg/min. Using the energy density difference (2.75) you get 0.073kg of H2 per min. Assuming room pressure and ideal gas law (sadly H2 is not an ideal gas but lets use it anway, i'm lazy) you get 22.7 liters of gas per 2 g of hydrogen. So, after that bunch of math you get 825 liters/min of uncompressed gas.

This amount of gas would be difficult to store, at 2500 psi this is the equalent of 1 gallon of volume, so it would take a big, heavy tank to hold something useful

The other issue with using hydrogen is how to make it in real quantities. The best available methods right now are electrolosis which uses

 

With most of the systems producing between 8-10 lpm of hydrogen, that just doesn't add up to any noticeable difference from the 800 lpm it would take to make the equivalent in gas.  So it would be like you substituting about 1 - 1.1% of your gas after the $500-$1000 cost and hassle; you could do better than that by removing extra dead weight out of the truck or buying some low energy tires.