well it depends on who you talk to weather or not the o2 extenders work personally I dont think they do, but it doesnt hurt to try, a good estimate on hho production is about 1 lpm of hho per 1 liter of engine displacement, now some say that its half of that but i think that you cant go wrong with one liter per minuite, also, ifthe extender doesnt work you should think about installing an EFIE for the o2 sensor and that will get you some gains, if you want to know more just pm me and i will talk to you, I havent figured out yet how to pm form this site so just hit me at
billhac2003@yahoo.com and I will talk to you more.