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Mass air flow calculation

EFI Tuning Fundamentals

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Calculating mass air flow at a certain rpm at WOT on a naturally aspirated engine, assuming that the VE is at 100% to approximate the injector pulse width for a starting point is simple.

But is there a way to calculate the mass air flow or VE at a certain manifold pressure where the throttle is not at WOT (cruise) or when there is a overpressure (boosted engine)?

Air density would change, that can be calculated fairly easy, but the mass air flow?

It would be awesome to calculate that for a starting point and then adjust while looking at the lambda.

I built a spreadsheet that would calculate Grams per Second with "knowns" and some "assumptions" when I worked at Identifix (Automotive Technical Hotline for professional Technicians in the aftermarket).

https://docs.google.com/spreadsheets/d/e/2PACX-1vRG0AcwTMfyHGbG9fiJbPEmhIDt0W6SJsk7I5EMaH9454q3ilrgYjT1YpDg1-s3QOUFq7dhvsSPryyk/pubhtml?gid=0&single=true

Engine Displacement in CC

Engine Displacement in Cubic inches

RPM

Engine Vacuum

MAP Absolute

Barometric Pressure

DR

Assumed VE

CFM

g/sec

Lb/M

Kg/h

3500

214

715

20.5

9.1

29.6

0.307

0.75

10.18

3.96

0.5234

14.24227779

3500

214

2500

23

6.585131579

29.6

0.223

0.75

25.79

10.04

1.3265

36.09496747

75% VE

Varibles to be adjusted are in Yellow

G/Second reading you should see on the scan tool

Assumed VE

Calculated values

75% VE WOT

3500

213.6

7000

0

29.9

29.9

1

0.75

324.45

126.27

16.6873

100% VE

3500

213.6

6000

0

29.9

29.9

1

1

370.81

144.31

19.0712

Corrected Baro

30.1

Altitude in Feet

500

Baro Correction Factor

0.982894737

75 EV

100 VE

UnCorrected Baro

29.58513158

Calculated Load?

0

0

How can I edit or put new values in that? Excel?

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