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
 * Calsulate

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

where according to the values in following Table.


 * Calculate manifold absolute pressure

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


 * Calculate mass air flow

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