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Old 12-07-2010, 09:18 AM   #174 (permalink)
dcb
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pimp mobile - '81 suzuki gs 250 t
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I don't know about that whole tap dance there, glad I could clear up how bsfc charts are used for you.

But weight is a much more consistent unit of measure when dispensing energy, as you can see from that scatter plot, hydrogen at various pressure (or temperature) levels contains the same energy content for a given amount of weight. Hopefully that is intuitive.

And it is also interesting to note that your 200-250 bsfc numbers (which was NOT power/gallons, in case there is still confusion there no thanks to mech) clearly put the improved efficiency of diesels in a new light. Despite gasoline having slightly more energy by weight, gas engines are frequently found with %25 worse fuel consumption at peak bsfc, per unit of power output.

Brake Specific Fuel Consumption (BSFC) Maps - EcoModder

What the bsfc charts are telling you is that, for essentially the same ENERGY input, diesels are still more efficient. You need to rethink your diesel assertions.
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