Firstly, a hydrogen fuel kit is essentially an on board device that generates hydrogen on demand. The source of the hydrogen is water. The way hydrogen is extracted from the water is via electrolysis, which involves running an electrical current from the alternator of your vehicle through the water reservoir which will split the water atoms, releasing hydrogen and oxygen. This gas, which is a mixture of oxygen and hydrogen is then transferred via a tube to the air intake and is drawn into the engine along with the air. It is within the conduction chamber of the engine that the hydrogen fuel kit affects the burning patterns of your fuel and increases your efficiency.
So, how exactly can using vehicle power to split water into hydrogen and oxygen, and then feeding these gases into your combustion chamber possibly increase your fuel efficiency? The secret lies in the fact that the average internal combustion engine is exceedingly inefficient. It is because of this inefficient extraction of energy from your expensive fuel that the on board hydrogen fuel kit can help you save gas. The new gas savings occur because by feeding hydrogen into your fuel air mix, you will increase the efficiency of the burning of fuel itself.
More than 50% of your fuels power is lost in the form of heat, vibration, and non-burnt fuel. It is from this 50% deficit in efficiency which you are drawing the extra gas efficiency by enhancing the burning of the fuel. When more of your gas is utilized due to the inclusion of hydrogen, your car can run on a leaner fuel air ratio.