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Calculating MAF values?

If I have the following MAF scaling:

Code:
V 0,0000	1,5006	1,8526	1,8623	2,2631	2,7226	3,0648	3,5438	3,9642	4,2819	4,5849	4,8049

MAF 0,00	         18,40	22,40	         24,20	41,00	         75,20	118,60	211,40	325,30	429,80	541,40	627,60
is it then possible to tell anything about when I will outflow it? (Let's just say I'm at 2500 rpm, 89% VE on a 2L engine).
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Yes it is possible...

Take engine capacity, multiply by air density (lets say 1.2g/l at 20C), multiply by engine speed (2500rpm in your case or 7000rpm if you want to calculate at red line). Divide by 2 (because engine needs 2 rotations to pump whole capacity). Multiply by VE (0.89=89% at 2500rpm, maybe 0.8=80% at 7000rpm).
At this point you have airflow in grams per minute.
So to get airflow in kilograms per hour (which is usually standard) you need to multiply by 60 and divide by 1000.

Which tells you that you have 160kg/h of airflow at 2500rpm, or 403kg/h airflow at 7000rpm (assuming that prediction of VE=80% is about right).

So with 627kg/h specified max airflow this MAF should be quite good for you.

You would need to spin the engine over 8000rpm at 100% VE to outflow this MAF.
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Quote:
Originally Posted by TribesMan View Post
Yes it is possible...

Take engine capacity, multiply by air density (lets say 1.2g/l at 20C), multiply by engine speed (2500rpm in your case or 7000rpm if you want to calculate at red line). Divide by 2 (because engine needs 2 rotations to pump whole capacity). Multiply by VE (0.89=89% at 2500rpm, maybe 0.8=80% at 7000rpm).
At this point you have airflow in grams per minute.
So to get airflow in kilograms per hour (which is usually standard) you need to multiply by 60 and divide by 1000.

Which tells you that you have 160kg/h of airflow at 2500rpm, or 403kg/h airflow at 7000rpm (assuming that prediction of VE=80% is about right).

So with 627kg/h specified max airflow this MAF should be quite good for you.

You would need to spin the engine over 8000rpm at 100% VE to outflow this MAF.

or have enough boost

Seems the MAF if capable of detecting enough flow - now I need to find out wh my ECU never uses values above 900mm^3/r. :/
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Do you mean fuel or air? Maybe you mean 90mm3 of fuel pre injection. What ECU type do you have?
If its EDC15, try to have a look at you last column in "smoke limiter airmass" map. It seems, that you dont calculate with 1200mg air or more. Adjust range. Or is it EDC16?
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Quote:
Originally Posted by sarkan View Post
Do you mean fuel or air? Maybe you mean 90mm3 of fuel pre injection. What ECU type do you have?
If its EDC15, try to have a look at you last column in "smoke limiter airmass" map. It seems, that you dont calculate with 1200mg air or more. Adjust range. Or is it EDC16?
I mean air, and yes I had tried to rescale the MAf axis beyond 900, but the ECU never used any values above 900. But I got it sorted, there were a SV that I had missed. Now I get to use the (new rescaled) smokemap. Highest recorded MAf reading was 1450 (well it was higher, but since I had set the plausability to 1450, I didn't get to see if it was higher) at 2400 rpm.
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