Thread: MAF Voltages (VQ Table)

Thanks, I forgot the B13 maf's where different! Added a distinction, B13/B14 DE. Added SR20VE to the VE one, and added S13/S14/GTiR mafs to the list. Gotta find a bored DE maf now .

In theory you would think when using a bored MAF you should be able to just add the percentage difference in area to the kvalue and then use STFT (short term fuel trim) vs MAF voltage to modify the VQ table.

You should be able to do this since the kvalue is just a maf scaling number.

I've seen dedicated tunes for bored DE maf, but different K value would make sense.

In theory then, using a Z32 maf element in 3.5-4" pipe would have the same values just a different K value right?

any for the bb maf?

I haven't tried anything like that before, but changing the Kvalue should still be the best way of accommodating for the extra flow to get it in the ball park.

If anyone thinks I am off base here, please let me know. I am definitely more familiar with map sensor based vehicles, but from my understanding the kvalue would work the same basic way.

The BB maf should be the same as the GTiR maf that is listed.


BTW, the Q45 and GTiR mafs have the same value in this spreadsheet. The GTiR values are correct, so double check the Q45.

That's exactly what I was thinking when cory asked the question. The wire stays the same, the programing/chip stays the same. You do increase the size thus the amount of pressure/speed that air travels through the wires is less/slower, but volts should be the same.

That's a hard one to answer. I can see logical points from both sides. I guess we need someone more MAF knowledgeable to answer that .



Looks like values that Evlnxr provided for Q45 where E60 ones at first, then GTiR ones.

I have not done this yet either so I might be wrong. But I would think just changing the k value wouldn't solve to problem. The k value is a global linear change and the maf new voltages would be exponentially different as the flow increases... hopefully someone who has done this can chime in... please haha

I think the percentage difference could be used as a starting point, but a more direct comparison of STFT and maf voltage is definitely going to be the best way.

I haven't had a chance to tune any cars with a bored MAF, if I do I will post up the results.

Agreed, VQ table just takes the volts and translates them to a number that ECU understands. Now unless the voltage itself will change, Kvalue will be what we need to modify.

Edit found a Q45 VQTable, looks like it's an E60 maf.