OBD-based emissions/fuel use calculations

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The RPM value used in the calculations of this section is obtained from section Maximum Acceleration (rearranged to solve for engine speed).
 * Calculate VSP, from section VSP-based emissions/fuel use calculations
 * Calculate

$$ MAP\times RPM=min(a\times VSP^b\times c,d) $$

where according to the values in following Table.


 * Calculate manifold absolute pressure

$$ MAP=\frac{MAP\times RPM}{RPM} $$


 * Calculate mass air flow

$$ MassAirFlow=\frac{MAP\times EngineDisplacement\times\frac{RPM}{60\times EngineStrokesPerCycle}\times EngineVolumetricEfficiency}{1545.349\times (EngineIntakeAirTemp+273.15)} $$