Stumble after rev in park/neutral

2009 CTS V, BTR stage 3 cam, 102 TB, 1050x injectors, etc. it?s pretty well dialed but one thing. If I rev the throttle in park/neutral the engine nearly dies when the rpms come back down. It recovers but it usually stumbles down to 500 rpm them settles back up to the set 750 rpm. Which parameters do I play with to fix this? Thanks.

Post your tune and log----hahahahha. I hate doing that, but. More idle air screw in the lower rpms ?

there are several methods to remedy this, as mentioned post your tune