How can I see what my timing is actually doing....

[dsatchell]

Does TunerSudio or MegaLog show what the actual spark value is or just what it is supposed to be? I'm looking at a knock control unit that will retard timing but I'm trying to find a way to datalog when the spark event actually occurs as compared to when MS says it is supposed to occur.

Any ideas or info?

[jcarruthers]

TunerStudio shows what it is? What is the difference?

As long as you've checked it's accurate with a timing light at a set point (TS says it's 10 degrees and you can see it's 10 on the crank etc) then that's what it is?

[LT401Vette]

TunerStudio reports what the firmware tells it, which is typically what it is commanding, so it would be what it is less any error.
Naturally it would not know the error or it would have corrected for it, typically the error is simply that it isn't set up right. So you should check that what TS says and a timing light match and correct it if not.