What exactly is the point of trying to get the BLM/INT values to 128 if all of the BLM/INT values are staying within 108-160 at all kpa?

Example: if you are driving down the road and the BLM is at 134 and the INT is at 130, these values are not at the max. Therefor at this particular instant, then engine is recieving the correct amount of fuel.

If all of the other values are similar to this example, then why is it so important to get them to 128?

 

BLs/Ints, are steady state corrections. While they'll trim the AFR to 14.7, none of those corrections get applied to Accleration enrichment, WOT, or DFCOs. So the closer you are to 128 the closer you are to having all the fueling characteristics correct.

If you're doing a complete calibration, you'll see where things work out much better by having things centered in the corrections, so under any wierd situation you have roo for the adjustment to go richer or leaner