Time to tell my secrets, I guess :secret:
As a quick baseline, if you start with my [THREAD=42711]No Logic 3.0 tune[/THREAD], you can look at what I did to the Injection Timing ECT tables ({B0911} through {B0915}). You will notice they are NOTHING like the stock tables. For example, {B0915}:
Stock is on the left, the smooth one on the right is mine. I have no idea what GM was smoking with the stock LB7 tune, it is garbage in the cold.
The real trick here is not the values in this table. We don't actually care. What we want is the
final injection timing to be reasonable. I made an Excel spreadsheet to add (some fraction of) the ECT modifier on to the base timing, and show what it will be. Better still, the spreadsheet lets you put in the desired final cold timing and your current hot timing, and it will generate this table for you. I have attached that spreadsheet (Misc Tools.zip), you want the "LB7 Compensator" tab. I make no warranties that the rest of the crap in that spreadsheet is any good, I wrote it randomly for who knows what, so use carefully and please don't judge WTF I was trying to do.
So go ahead, grab my tune, use the spreadsheet, and see what the final timing I was going for is. That is a reasonable start for a stock injector LB7.
But wait, there's more! I attached my current built motor tune, which has SAC 75% injectors and a big stupid cam. Do the same thing with that tune and see what I was going for with timing there. Tom, you probably want your timing somewhere between those two values.
The other big table you need to concern yourself with is {B1002} Fuel Pressure ECT. Do the same trick (with the Excel sheet) to see what final values I am targeting on a stock and built motor.
Oh, and if you see the "Modifier Multiplier" in my spreadsheet, that comes from the "<whatever> Multiplier" table that matches the name of the above tables. You can play with that to adjust how strong the cold engine compensation is for any given coolant temperature. See how I played with that too in my tunes.
Finally, there are a few other tables to look at to get it to start and run nice in the cold. Everyone,
please adjust {B0731} Cranking Injection Quantity if you have larger injectors. That fart of black smoke when it lights off isn't cool, this isn't a Cummins, let's get things running right, not fart-y. And the last few are your pilot quantity and timing tables, which have ECT references as well. That usually isn't as big of a deal.
From what I found, the various IAT referenced tables don't work, even if you populate them, sadly. Hopefully this helps!
