Interesting, I did not know there was so much to the fuel gas requirements. I have not had to worry about the gas value as we have "pipeline" gas for fuel.
A correction on the Superior engines, they were originally made by White-Superior, and then when White had problems Superior was sold to Cooper, in the 80's I think. The time line gives the start date of all the original companies that are now in the Cooper company.
As Superior is almost a dead company, a couple of aftermarket companies may have more information. Sinor Engine, and EnDyn both support the Superior engine aftermarket.
If the BTU value, or the LHV doesn't swing too much I would think you could adjust the engine to run correctly.
Can you expound on your problems more?
dwedel
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