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Does anyone have any experience with GM LS2 idle tuning?

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my idle is all i lack to finalizing my tune while i have gotten it to idle around 850 fairly well with the spark adaptive idle on my spark timing jump quickly from 15 to 22 degrees and with a lack of tuning experience I'm not sure if this is normal. I have tried commanding it off but when i do my idle goes up to around 1050 and no matter how i tune the idle up or down it does not respond.

If your using spark adaptive idle control and it is stable at the target value then the jumping of 7degrees is nothing to worry about. As for the idle raising when you deactivate it, what does your timing go to with it deactivated?

With spark adaptive idle off my spark timing goes to a steady 22 degrees

What you're seeing is totally normal. The PCM is using the ignition advance/retard and the subsequent affect on engine torque to help control idle speed. This is common place on most late model OE ECUs and typically an option on many aftermarket ECUs. We used to offer a service on many of the LS engines we tuned that we referred to as 'Ghost Cam' where we simply increased the range of adjustment the ignition control was allowed. This resulted in large timing swings at idle that offered a 'lope' similar to a mild cam.

This is based on a Link G4 ECU, however here's a webinar that explains the principle -