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Lbs / min of airflow = -0.0484(V^4) + 1.0634(V^3) - 2.8255(V^2) + 3.7958(V) - 1.6926

5 volts is ~49 lbs/min on the OBD2 logger. The scale may not be 100% correct on this formula, but the curve is.

From what Ash Powers told me (I don't know if you have heard of him, he does some ECU reprogramming for the Z32s) your stock turbo MAF flows better and meters just as much as our stock MAF. I did see a spot in the software he was using where you could re-define the lookup-table used to generate the load value.
 

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toypro said:
Do the mkiv's use a hotwire maf meter? If so, I don't think you'll really be able to find that information unless someone had logged it on their own,and that would not be accurate either. If it uses a hotwire MAF, it bases the voltage output of the sensor on the amount of current needed to maintain a constant temp to the hot wire, don't know exactly how to explain it, but basicly has a wire kept at a certain temp, the more air that passes it,the more it cools and thus the more current it needs to maintain the required temp, the sensors output signal is determined by the current flow required to do that, not by the auctual volume of air passing through. Assuming you're talking about a turbo model. I don't have a mkiv, but I'm fairly certain they use a hotwire maf, if not sorry.
Yes, both the Z32 and MKIV turbos use hot-wire mass air sensors. The formula I posted was taken from readings from a voltmeter and corisponding readings from a OBD2 datalogger. I am 100% sure the curve is correct, although the overall scalling might be a little off. If you look at the equation you see it is far from linear.

Note that GM mass air sensors have a frequency output, but are still hot-wire type. Supposedly GM did this for better noise resistance.

Hot-wire mass air sensors indirectly measure the MASS of air, as Toypro said. This is why they can be used in blow-thru setups. Thus my units are in pounds per minute. If by "volumetric quotient" you mean a chart of volume versus voltage, then those are the wrong units (although its obviously convertable).
 
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