rpm bog when placing into gear.

[98goldta]

well the tuning is coming along pretty well , for my first time. does anyone know what parameter to adjust to work with the idle stumble when you select reverse or drive from the park position. the engine is an ls1 that i have running the ls6 cam and intake and mildly ported ls1 heads. The cam would be the 551 lift version. stock maf and stock throttle body , but I cleaned up the tb a little ,nothing drastic. I am using ls1 edit for my changes and I have made adjustments in the maf table as well as the high octane and base timing tables , but nothing has changed the stumble. the rpm drops to about 400 from 650 and then back to 550. I have a new converter that is stalled to 2000 with lock up and all also. This engine is not over built and I would think it should idle fairly smooth for a stock ls6 set up. but at low idle it is kind of rough and I get an ocasional misfire while stopped in drive. Is any of this because the pcm hasnt relearned all the cell ranges yet? So what are your thoughts?

thanks for you help in adavance

greg

[Frost]

It needs idle airflow tuning. You need to log for desired idle airflow plotted against temp so that you can populate your own idle airflow tables both in and out of gear. You can log trimmed value and apply it as correction, but it's easiest to use desired.