I'll offer, to anyone on this forum who has a functioning HHO system, to dyno their car for free to show the effects on performance. And then to publish the results on the forum.
I don't have my mileage test rig working yet - later this spring.

-Jo

[first come, first serve, one-time offer]

 

now we're talking, if that person had megasquirt going with full ignition control and wideband o2 sensor it would really be cool.
there are other ways of producing hydrogen on board as well, plasma is supposed to increase h2 output . i know even less about that then the pulsed dc variety.

aluminum, lye and water too, exothermic, consumes both water and aluminum.

it may be that the 5% required(per roy mcalister, corrected from 4% stated previously) is by btu, while not confirmed this is a significant amt of h2.

Consider this as well, if one were able to store this gas on board and produce at home, it would still be of a benefit, your own plug in hybrid of a sort.

because, honestly, i don't see anything other than the tesla motors hot rod that piques my interest.