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To create that landscape, we turn to one of the C-Com's numerous customizable tables: Fuel Ratio vs. RPM & MAP (manifold absolute pressure). In speed/density mode, the ECU first determines the volume of air being consumed by the engine. Then it looks to this table to determine what air/fuel ratio is the target and how much fuel is needed to hit it, and then makes any necessary corrections. The target air/fuel ratio table is a critical part of the calibration in speed/density mode, but the optional Alpha-N mode does not use it as part of the base fuel calculation; it simply references injector pulse width from the base fuel table. Got that? Don't worry; it's all in the book.