There is so much on the internet regarding hydrogen power.  I've read for hours and pages and pages of info before I got into it.  I've made my own and made enhancers (computer).  I can tell you this, the very best I ever got on my VW beetle was -4miles per gallon.  Yea, minus.  The problem is is that the motor has to turn against the draw of the alternator, which is powering the generator.  I've even tried it with and external battery.  It's not worth it, it's not worth the time, aggravation or money.  I just can't believe some of the forums and the claims that are being made.  Hey....if it sounds too good to be true it probably is.