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Doing all research and tuning myself, partly because I like to dig into stuff I know nothing about, mostly because im out of cash... According to the sites EVERYONE on here points me too, I should adjust the spark advance up one degree at every point untill I start seeing knock retard on my logging program, all makes perfect since, except for knock retard is code for wear on the engine, so the engine adapts and retards the spark, so I gotta get this right.. Simple question,
If I get spark retard at 36.9 KPA 1350 RPM's should I be changing the table at 1200 or 1400 RPM's, 35 or 40 KPA's? If I log .8 spark retard, does that mean I can take that cell down .8 in value and everything should be perfect?
 

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All tables rows and columns are the starting point, so in you example the RPM row labeled 1200 is for RPM's starting at 1200 and going to 1399. And the MAP column labeled 35 is for MAP starting at 35.00 going to 39.99. You would change timing in the 1200/35 cell for your example..
I would look at "knock count incrementing" not at the spark retard. As the PCM remembers where knock has occurred and it will pull timing at that spot as a preventive, even if knock is no longer occurring. That retard will fade after a while if no further knock occurs at that spot. IMO doing timing w/o a dyno is tricky as you will hit a spot where more timing is not providing any more performance. Hard part is knowing when to stop adding. If you look at the timing tables, opening main and extended on the same screen and looking at then as a single table the upper left quadrant is low RPM no engine load (idle) , upper right quadrant is low RPM high engine load (bogging) , lower left (5/29/13 corrected from typo saying right) is high RPM no load (deceleration) and lower right (5/29/13 corrected from typo saying left) is the go fast high RPM high load (WOT). The high end timing varies in each quadrant. I personally never played with fractions of a degree, like .8 it seemed to granular. If I have knock in a timing cell I would drop it 1-2 degrees and maybe 1 degree on cells around it. Again the quadrant it occurred in low or high load would assist my decision.
 
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