Gen3 idle

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Stock LM7 with Brian Tooley truck norris cam and long tube headers. My STIT continues to pull air flow out and will never become stable. When i do a cold start once it gets into the 176 cell it wants to be in high 50s airflow. The longer it runs the lower the desired airflow it calls for, to the point of getting into the mid 30s. MAF is within 2% at idle, IAC counts are 30 to 40, idle timing is max timing for lowest vacuum and mass airflow is around 1.0 lbs/min. I've tried 15 18 22 25 28 30 on timing and no change. Tried idle target 700 750 800 and no change. The lower the air and timing the worst it runs. It idles very well 750 rpm, 30 on timing and high 50 for airflow. Once the ECT starts to become stable STIT start slowly pulling airflow. Is there a possibility the ECM is faulty? Could injector timing play a part in this problem? Could long tube headers be playing a part in this problem? Or could they be a prombley with my laptop?

[5FDP]

This isn't a small block chevy, they don't idle at 30-35 degrees of timing. Turn that way down to 20-22 degrees.

Get bigger injectors, can't really do anything with teeny tiny 22lb/hr injectors, it'll be out of fuel at 4,500rpm if that.

I'd get new injectors, lower the timing way down. Return the base running airflow to stock and just add like 15-20% for starters. Then tune both VE tables and MAF tables to get fueling down, then see how the idling does. No sense in doing things twice when we already know that this engine doesn't even have the injectors to support the power this engine will make.

[DougO]

I'm at 23* idle timing,11.25 grams of air at operating temps, VE, MAF are within 2-3% and I'm pulling 3 grams stit, idle at 750, mine seems to idle great, I'm still on stock injectors but replacing them with 50# gm flex injectors.

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Customer has a set of 30lbs injectors order. At 5200 its 80% duty cycle. Thanks for the info!!