Just as an example, here a legible BSFC map. What is the scale of the Iso lines and how can they be shown as higher than the torque curve? Do any of the lines necessarily show 100% throttle? I am assuming the 250 line is centered around 95% throttle lets say, and the 275 line is the constant fuel consumption Iso with 100% throttle across the top which happens to blend to the same consumption with lesser torque output and a lesser throttle opening of 85% (or something) around it's lower portion.
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