There are many factors involved in whether an HHO generator will work well or not. The major factors are:
1. what are the electrodes made of, how well will they conduct electricity and how quickly will they corrode?
2. What electrolyte mixture are you using in the water (electrolyte is required to make the water conduct electricity to split the hydrogen and oxygen)
3. how much oxygen are you involving in the gas out to the engine?
4. How many o2 sensors does your vehicle have and how will they react to the extra oxygen they will detect? (sometimes the o2 sensors will detect more oxygen and increase your fuel ratio to compensate for it – I personally have not had this problem, but have heard others record it)
5. How much volume of HHO gas by LPM are you making available to your engine and compare this to your engine’s size.

Speaking from my personal experience with the generator I built, I have literally TRIPLED my gas mileage.

Potential hazards include:
1. Chance of exploding HHO gases if mis-used.
2. Blowing fuses.
3. Water damage to the exhaust over time.
4. Water in the engine – if you are really really careless.

If you are interested in copying any of our designs for personal use, we have FREE diagrams and plans on our myspace page: http://www.myspace.com/trinityenergies
We also have an FAQ’s page and an HHO Hints and Tips section.
If you need any help along the way, don’t hesitate to ask. We also have installation instructions available for free upon request.

References :
Experience. We are an Alternative Energy Research group and have over 100 test vehicles to date.