ToddnMiss - Reinhart has a theory about the point range of MAF's that claims that bigger is not necesarily better.
If you care to read it - here's his summary:
Mass Air Flow Meters
I get a lot of calls about Maf's. The Mustangs have a good Maf, but it can also do real well on the Lighting 80MM and 90MM depending on your Mods, Now there is a new Maf out that is 85MM on the new 02 Mustangs (YC2F-12B579-BA) and for N/A cars it works better, let me explain.
The lightning MAF (XL3F-12B579-AA) has a Max range at 5 volts of about 56 #/min of air. The Max amount varies depending on how you mount the MAF and the bends before and after it. This is critical if you have sharp bends in front of the Maf it will throw off the air meter transfer function. And if you gut the air box and put a conical filter on the end of the Maf all you end up doing is sucking in very hot engine air, which can cause spark knock and detonation.
The MAF in the 02 GT Mustang's is the exact same housing as a lightning MAF it has the same pressure drop as the lightning MAF, but revised electronics. At Max voltage that MAF has only 46 #/min of air flow.
Now, when you look at an N/A car like most of yours, you'll only use about 35#/min of air peak. So, if you put a lightning Maf in you'd only be using 35/56 or 63% of the MAF. So With GT MAF you'd be using about 35/46 or about 76% of that MAF. On a car like a non PI head 4.6L, you will see a peak air flow of less than 30#/min.
Why is this important? It has to do with fuel control. The air meter transfer function has 30 points to it. It's a function with 30 points from 0 to 5 volts. If this range of 0-5 volts is 0-56#/min and you are only using 0-30#/min of it, you won't have good enough fuel control since you are only using about 1/2 the air meter range.
REGARDING THE CRANK PULLEY
Does that big old can stuffed into the center of the crank pulley get in the way of a different size pulley? What is that thing anyway?
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