Check for details. 90 MPG Car - Nissan Altima Gets DOUBLE Gas Mileage with HHO Kitbr br Get step-by-step instructions how to Convert Your Vehicle into a Hydrogen Hybrid and br SAVE TONS OF MONEY on fuel costs.br br Hydrogen Hybrid Conversion Plans show you how to build and install your own Hydrogen Generator System (HHO Generator), which produces Hydrogen "On-Demand", as you need it. This technology has proven to increase gas mileage by as much as 150 on both gasoline and diesel engine vehicles.