well, an ocd guy just has to tweak his maf table a bit, that's just how it is.. if for no other reason than to be one step ahead of closed loop operation, so it doesnt take any time to correct your AFR. and hell, this thing is used as the metering device for power enrichment, so when you go to tune that, if you have your maf table nailed so you get 14.7:1 at higher rpm out of PE, you can hit your final power enrichment targets way more easily.
once you tune your maf wideband in open loop properly, your blms WILL be pretty much garunteed to be close, unless the o2 sensors are screwed.
so your BLMs, are they 108 the entire time, or are they 108 only in cruising cells? that's kind of important.
always remember what a BLM value really is. you're working with a 4x4 grid of cells, each one specifying a range of operating, rpm on one axis and MAP on the other. the data in these cells is based on averaging the short term trims.
the value itself isn't as important without a frame of reference, knowing what cell you're in, and what range of operating it covers, for example if you're hitting 108 in cells 17 and 18 (fairly common) it doesn't matter. i made this chart so you can visualize an LT1's BLM system:
http://resfilter.net/files/carstuff/...ell%20Grid.pdf
the boundaries between the cells are tuneable, my XDF has two tables in air fuel metering > block learn mode, BLM cell RPM and MAP boundaries, and they're labeled appropriately to that chart so you can figure out where you stand as far as what cell is what, and how you can improve them.
it's also worth viewing a datalog to see how many log events happen in each blm cell. if you're only getting a few events in a cell, you should move your cell boundaries so all cells are being used for something. having a good range of operation is a good thing; that means if you have a lean area next to a rich area, they wont average into the same cell
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