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This post IRT the picture of your spark table:
I almost always make the columns the same between 0 RPM and 1000 RPM (your first three sections) to cover the idle - usually reduces fluctuations, corrections, and smooths the idle.
If your X axis is actually in inches of HG, then
cranking will start out at Zero vacuum and "pump down" (towards the left of your table) from there to about 12-ish. So if you can imagine the load cell moving from the zero-RPM row and zero-vacuum column down to the 500-RPM row and to the left, jumping in steps of vacuum as the manifold pressure goes through it's pump-down while cranking.
Your first two rows (0-RPM and 500-RPM) should indicate your desired cranking spark from the 13.5"-vacuum column and to the right. That is unless your ECM uses a separate table for just cranking spark, and/or another cranking spark modifier constant or table. There is usually at least a crank modifier table based on coolant temp, so that must be taken into consideration when determining your cranking spark values on your main spark table. A good warm cranking spark value is usually between 6* and 10*.
The 0-RPM through 1000-RPM rows, from 13.5"-vacuum and to the left should represent your desired idle spark. I usually start out by making all of those cells 20* and start from there - experimenting to see what the engine likes best.
The lower left quadrant of your table looks fine. That's all heavy DECEL and/or DFCO area.
Your load cells in the range between 17.44"-vacuum, 7.6"-vacuum, AND 1000-RPM, 2500-RPM (inclusive) is where the meat of your driving will be and will require the most work to get right.
Generally speaking, it looks to me that this area does not drop off quick enough as you move to heavier load cells (towards the right) starting from about the 13.5"-vacuum column. As I said in another post, there should be a fairly steep slope somewhere in there as the load increases from light-cruise, to light-ACCEL, to heavier-ACCEL during most of your normal driving. The lower the RPM, the more sensitive to loading the engine is, and the steeper the slope between one load cell and the next load cell beside it (left-to-right).
Your SA values are only changing one or two degrees as you move left-to-right across load changes in this area of normal driving. That's the biggest problem I see. Without driving your car and watching test equipment I can't tell you for sure where the big changes need to start, but:
If your steady light-cruise is around 13.5"-vacuum, then you will need to reduce your SA numbers in larger steps in the columns to the right of 13.5".
I can imagine a progression from your 30* SA at 13.5"-vacuum down to 18* or 20* by 7.6"-vacuum.
That's my best remote guess to give you an idea the basic shape to shoot for.
A knock sensor will be helpful, but you can do it by ear if you're careful. If you find that your ACCEL isn't causing knock even though your SA values are high, then suspect you have an AFR that's too rich.
The richer the AFR, the less sensitive it is to spark advance changes. I'm guessing that any loads higher than 7.6"-vacuum will be covered by your Power-Enrichment (PE mode). Generally an AFR between 12.2:1 and 12.8:1 will cover PE up to around the zero vacuum point.
The rest of the table should be fine, assuming your PE mode covers 3000-RPM and up.
Best I can do from a distance.
HTH.
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