Very nice posting because I have exactly the same car and motor. I have already build in a 1 liter-system. The results are not good so far. Without dry-cell the motor takes 1 liter gasoline per 14.6 kilometers. The short first test that I did gave 1 liter gasoline per 10 kilometers. My question is, do I need an EFI or something for this single point injection motor with 1 lambda sensor (1 lead) going out of the motor to the catalyst. Is it possible the sensor 'says' your mixture is to lean because of the high amount of oxygen in the HHO mixture. Is it possible the fuel injection drops to many gasoline? I noticed more power from the engine but for more gasoline it is a waist of time.