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MAP Tuning for a COBB air intake

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Hey all!

I finished scaling my fuel injectors and now I'm moving on to my MAF scaling.

two quick questions:

  • what do you find as the most effective way to scale the MAF at idle and cruise? I'll be using Rom and ECU flash.

  • I upgraded to the COBB airbox and intake. In comparing the area around the MAF from the OEM to the COBB I literally see no difference in measurement. The area of the circle around the MAF sensor housing is negligible. So with that being said, my question is: What am I actually scaling when it comes to MAF?

  • Hoping to hear someone else's iterative process and get some ideas on how to move forward with this before I start tuning light loads and WOT.


    2004 Subaru STi USDM; upgrades ID1050x and COBB air intake with box.

Also, I forgot to mention.

I shut off my rear O2 sensor and will be using a serial input for my AEM UEGO sensor so that I can target the right AFR.

J P,

The ID measurement is a good starting point, but the flow potential is rather different and the MAF scaling becomes very different at high airflow as you'll find.

HPA teaches MAF scaling in their practical reflash tuning course which also teaches the various other processes you'll need for your reflash tune. Have you taken that course yet?

Yes, I have. I have taken the Tuning Fundamentals course, the Understanding AFR, and now the Practical Reflashing course.

The practical reflashing course has helped me dial in my fuel injectors, scaling, and latency. However, I still have questions on MAF calibration, scaling, equipment and just simple nuances when one is new to tuning.

Is this the wrong forum to ask these questions?

We usually reply within 12hrs (often sooner)

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