Hmm, I just recieved some interesting news. A friend of mine just told me her brother-in-law told her that his friend put a Hydrogen Generator on his truck and got 7MPG better. I'm going to try to arrange a meeting with this guy and see weither he built one himself or got ripped off online with a $500-$1000 unit.
As for now, I'm just speculating, I'll post more as I either hear more about it or get to see the set-up.
If he built one himself, and is using nothing other than a HHO generator then this could be promising, but the chances of that seem to be around 5%. First off, he put one in his truck so he is interested in his mileage, but I doubt he did any proper testing methods. Most likely he put it in, got too excited, and filled up after 50 or so miles. My area is a large farming area so its mostly country with minimal stop signs, so those 50 miles would be counted as mostly highway mileage would could explain the increase. Also HHO Generators have been proven not to make a noticeable increase many times. I think its more likely that he ordered a kit that has an EFIE, MAP Enhacner, and possibly even an IAT resistor. That'd get his truck running lean and would keep the O2 sensor from adjusting back to 14.7:1. Even though I doubt running lean in a truck could make as huge an increase as 7MPG, it may have made it seem so with the Highway mileage and slight lean conditions.
I'd hate to shoot him down, especially if he spent a lot of money, but I feel he should be enlightened so he doesn't fall for scams. Maybe I can even get him on GasSavers. But I'll let you guys know as soon as I get a chance to check it out. I'm rather excited, it seems like HHO is turning towards McCarthyism. If you hear about someone using HHO you better run and set them straight or they'll be condemned when they go preaching it.
the fact is that a lot of his gains are probably coming from driving style changes and the fact that he probably didn't keep up with his mileage before.
one thing you could ask (though he probably won't do it) is for him to take the hydrogen generator off for a tank now that he is getting that mileage. this will prove or disprove the whole driving technique thing. you could also offer to pay for that tank if he gives you crap about taking everything off and his diminished mileage.
the key is to be gentle. people get really offended when you tell them that what they are doing is a crock or that it doesn't work. get him on gassavers if you can. if for no other reason than to start a gas log so he can see trends. numbers are good but it is hard to see a trend with a bunch of numbers. the graphs on here really helped me.
I am still verry weary of changing the o2 sensor readings and the IAT sensor readings. people have said that the added hydrogen helps keep detonation at bay but they don't have to by ME a new motor when mine blows up.
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