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Dude you need to use the same exact MAF as what was on the car originally. Just replace it with another KA maf and you'll be good to go. Note the DOHC and SOHC mafs are different, please be sure to get the right one!
This thread is fun and I'm bored, so I'll give you a MAF explanation so you can learn why this is. And have a better understanding of what's going on...
MAF newbs read up!
Each MAF sensor (ka/de, ka/e, n60, z32, q45, etc) has a unique calibration. This calibration translates an airflow measurement (#kg/s worth of air) into a voltage between 0v and 5v for the ECU. The ECU has a matching calibration table stored in it's memory (called a VQ table), so that it can quickly translate the voltage back into a measurement (kg/s of air).
Lets assume your stock KA maf was reporting 3.5v @ 5000rpm to the ECU. If you were to replace the MAF with a differently calibrated MAF, such as a Z32 or n60, it may only report 2.5v @ 5000rpm for the same amount of air. The ECU doesn't have any way to know you swapped the MAF, so when it looks up 2.5v in the VQ table for the stock MAF, it will only allocate fuel for "2.5v" worth of air, instead of the actual 3.5v! Obviously this is going to create a very lean mixture since you're short changing the motor on needed fuel.
Now during idle and part-throttle cruise, the ECU runs in "closed loop" mode, this means it continuously monitors the O2 sensor to see if the mixture is a little too rich or a little too lean. The o2 sensor is a fine-tuning adjustment. It uses this feedback information to fine-tune the mixture (short and long term fuel trim) a little richer or a little leaner.
But! During higher load & wide open throttle runs, the ECU switches into "open loop" mode. This means it completely ignores the O2 sensor output, and completely relies on the MAF sensor (well, along with RPM, TPS %, ECT temp, etc) to calculate fuel delivery!
What this means is that the ECU will have no way to know it's running too lean (except excessive knock & elevated engine temp, which will cause it to retard ignition spark timing which seriously reduces power output). It will most likely in due time melt a hole in your piston, or otherwise destroy the motor from knock/pre-ignition. Leaner mixtures burn hotter, and leave more heat in the combustion chamber for the next cycle to deal with.
Of course if you have a magical tool that lets you reprogram the VQ table in the ECU, then you have the freedom to use just about any MAF sensor you can get your hands on. This is how people are able to use N60 or Z32 maf on their "stock" ecu -- it's been chipped or reprogrammed somehow. Instead of reprogramming the ecu, some guys will run the Apexi S-AFC to use the z32 maf with stock ecu. This is a somewhat half-assed approach to tuning, since the ECU still has the wrong VQ calibration table. (sorry if anyone is offended, but you know it's the truth)
So for these reasons it's important that you use the exact same MAF as the ECU is expecting, otherwise you'll confuse it and it'll end up costing you your motor. In a less extreme case, you may not burn a piston, but you'll definitely have a bad idle, sputtering, trouble starting, poor acceleration and terrible fuel economy.. All from try to use a n60 maf when you should have just stuck with the KA maf.
The same logic is true for injectors, you can't just slap in a new set of 550cc injectors when the ECU is expecting 270cc's... Things have to be calibrated to work with each other, you can't just throw stuff together and hope it works. The ECU and it's sensors don't work like the USB port on your computer. If you install a new or different piece of "hardware" you need to put a new "driver" on the computer!
GL I hope you learned something about MAF sensors with this thread.
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