Haring Labs Commercial hydrogen system for 100 - 500 hp engines. ( Patented Technology) The system works on Petrol, Diesel, and bio fuels These systems are a very cost effective way to have older engines comply to the new emission standards. Why spend money on replacing engines when a simple, fast, retrofit can solve the problem of emission compliance. There also will be a reduction in fuel consumption  due to the increased efficiency in the burning of the fuel, results can very a little depending on engine type/design. Value added features also come with the system, the system is remote capable, such as GPS, engine monitoring and management, data logging along with WIFI and Cell communication. The system and engine can be monitored and managed threw the internet or cell phone via web site or phone app. The systems are adjusted to work with in the parameters of the existing engine set up, such as timing  and fuel trims, much higher gains can be had with the re-timing of the engine. There also may be fuel and tax credits available.