Ok... um... I know i shouldntBut I have to post my results. <<GEEK ALERT GEEK ALERT>>
I went back and retested before and after and came up with the same results. I flly warmed up my car to 80*c. I monitored AFR using a gauge on the dash page... because you can enable the min and max needles. With the stock injector timing settings, copied from the stock 20002 FBody LS1 tune, my AFRs bounced around at idle (like they always have) from anywhere between 13.8 to 15.8, giving me an average right about where it should be. I then used my logic above, and altered the timing to essentially fired the injector earlier. I subtracted.334ms from the injector timing because this equates to 2 degrees on the crank. I reflashed and restarted the car. I let it get to 80*c again and started my monitoring. Now, my AFRs bounce between 14.2 and 14.8. I thought I was seeing things, so I put the setitngs back and tested again... back to the way it was. Readded timing to the offset of .334ms and sure enough the AFR's are back to 14.2-14.8.
Hmm... it occurred to me that that 2 degrees on the crank is 1 degree on the cam, the injectors are fired off the crank sensor, so I should actually use more time... so for the hell of it I am going to try to add .668ms and see what happens. I really dont have an explanation.. but I thought I would share. My cam specs are 242/248 .613"/.617" 112+2. This cam with my 11:1 (or higher) compression ratio makes for a rough idle.
UPDATE: I tried lowering the timing offset by another .334ms and see the same result. Maybe slightly more stability but still definitely different that stock timing. Just to make sure, I put stock timings back again and saw the same bouncier AFRs. It is a good Friday.
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