The high consumption rates of fossil fuel and unburned hydrocarbons pollution in exhaust gases are considered to be the main problems that face the world today. The use of Brown's gas (HHO gas i.e. mixture of hydrogen and oxygen) as a new source of energy, reducing the amount of injected fuel and ensuring complete combustion of the mixture are gaining an increasing interest worldwide. There are two different types of HHO cells; HHO wet cell and HHO dry cell. In this paper, the HHO dry cell was used because it has several advantages, such as its small size and ease to install in engines. The HHO dry cell uses the electrolysis process in order to produce the HHO gas from water, which is ionized by adding NaOH as the electrolyte. Three types of HHO dry cell were used, namely alpha, beta and omega cells. Many measured data were done to choose the best one of the HHO dry cells. Oxygen sensor, MAP sensor, and MAF sensor were used to control the fuel injection. From the recorded measured experimental data, the beta cell has shown a good performance for the engine. The amount of HHO gas needed to be supplied to a 1500 CC engine is 0.375 LPM. The results also showed that there is a 17% reduction in fuel consumption and a 17% reduction in CO, a 27% reduction in HC, a 15% increase in O-2 and a 1% increase in CO2.