Subaru Maf IAT Correction

[jacky4566]

So looking at fine tuning a subaru MAF setup.

The stock IAT correction table looks like this: (Ignore the lower table)


As you can see the correction factor varies widely depending on the sensor flow rate, and it looks to be opposite across the spectrum so I can't simply flatten the table.


Has anyone run into this? How can i implement MAF/IAT correction based on flow rate?

[Matt Cramer]

What do the numbers actually mean?

[jacky4566]

Not sure of your question Matt. The table is a Intake temperature correction factor % for the Maf.

So @ 2.5g/s and 80c the MAF is corrected -2.3% = 2.4425g/s While
at @ 170g/s and 80c the MAF is corrected +5.1% = 178.67g/s

On the hot end there is a spread of almost 10%.

It's not really a big deal but if there is a way I can translate this in that would be great.

[Matt Cramer]

OK, so it is added to 100% and then multiplied by the air mass calculation. I was just trying to figure out what the number meant - it could have been directly added to the MAF reading, for example.

This isn't supported in the current firmware, but it's a fairly small correction factor in the overall calculations.

[jacky4566]

Gotcha. Yes this is how i have interpreted the table to work. I dont have a stock ecu to check.

Ok. Ill massage the current IAT and VE1 correction tables.