quickie tuning method

[WEG1192 at aol.com]

Let me run this by the experts. After my first tuning experience flopped (but 
I learned a lot), I started over with the stock Chevy 1/2-ton C-1500 bin in a 
7747. I drove my AMC 360 around and watched the BLMs try to make the thing 
drivable. All the BLMs were near 160 so I increased the BPW constant from 135 
to 170 (160/128=1.25; 1.25 x 135 = 170). Now the vehicle runs great with BLMs 
in the 120-128 range everywhere and 850-900 mV on the O2 at WOT. So the 
question is, can tuning be this easy? If not, how do you use BLMs to adjust 
the main fuel table numbers? The BLMs seem to be so broad that I don't see 
how to arrive at a change from one table value to an adjacent table value. 
For ex., consider an RPM change from 1200 to 1600 RPM at a MAP of 50 Kpa. 
>From what I can tell the BLM can't distinguish changes at this resolution in 
the table. Do you have to analyze O2 sensor volts to get to this degree of 
perfection? Or can you narrow the BLM range down to cover only a small 
portion of the fuel table to get to this resolution?

Second, the BLMs and integrator numbers climb to 135-145 during mild 
acceleration. Then once the transmission shifts to a higher gear the BLM 
drops back down into the 120s. Is this sudden climb and then drop normal? 
Does this mean additional tuning is needed in the acceleration pump shot? I'm 
not talking about a floored pedal launch but a smooth mild take-off from a 
stop light. There is no hesitation, just a temporary increase in the BLMs 
during the acceleration. I realize the BLMs might be jumping from cell to 
cell, but I see a gradual increase, not a drastic skip to another number.
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