Yeah you can play with it, I think GM kept a bit of a margin for error. +/- 4* across the board on a stock engine may or may not induce knock. Of course, yours isn't stock.
The ECM DOES do timing for you, should have 20-some degrees at idle with the bypass wire hooked up. Not talking about anyone here, but just in case, some people are under the mistaken impression that the ECM will run as much timing as possible before knock, which is not true. Timing is "mapped", and that preprogrammed map temporarily changes only when the knock sensor starts retarding it.
You need to watch your knock counts while driving under various conditions, if TBI allows the knock sensor to work when winALDL is hooked up. You may not hear knock even though it is occurring.
Timing is all about how the engine is built as to what it wants, since you aren't stock, it's entirely possible that a base of 0* isn't what the motor wants. "Problem" with advancing base is that it's a "global" change, so while 2* at idle may not be an issue, at WOT climbing a hill, that 2* might be enough to start the engine knocking. Obviously if it runs better off the line with more timing, but starts knocking later on, either you've got too much timing up high, or the fueling is wrong.
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