Lean shifts and gradual let off

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First the specs:
66 Chevy C-10, 416ci, DBC, 02' Fbody ECU, stock LS3 heads, Holley high ram intake, 90mm NW TB, 42lb/hr injectors, 58psi at the regulator, custom 1 7/8 headers, Cam Motion street grind- 226/236 @.050, 598/598 on a 117lsa, Tremec TKO500 5 speed, ls7 clutch

The truck is running pretty good over all. I'm getting RAF and VE table dialed in slowly but surely. The main issue is the engine going lean on shifts and cruising on slight decel when I back off the throttle a little. By lean, I mean pegging the gauge and misfiring.

Should I be looking at DFCO? If it's cutting fuel as soon as I let off the pedal will that cause it to go lean?

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Any thoughts appreciated. Going out to work on it today.
Thanks

[5FDP]

Do you have a wideband o2 sensor??

I'd try getting the MAF and VE much closer with the wideband in open loop first, then see if the lean issue is still there. Right now the computer is doing what it can to remove fuel with those really high negative fuel trims.

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Do you have a wideband o2 sensor??

I'd try getting the MAF and VE much closer with the wideband in open loop first, then see if the lean issue is still there. Right now the computer is doing what it can to remove fuel with those really high negative fuel trims.

Thanks! I drove around and did some logging and VE adjustment today. It's definitely better between shifts and now is only going lean when I'm cruising at a steady rpm, let off and slow down a bit then ease back into the throttle. It runs really strong and in the high 12's AFR when I'm deep enough into the throttle to hit PE. Not leaning on it too much till I can work out the lean condition.

I have a wide band hooked up but it's not logging. I still need to figure out how to wire it in through the ecu. I've read a few things but haven't had time to mess with it yet. MAF is next. Thanks for the input.

[5FDP]

I can't view your tune as it seems it might be done using the beta software but I will say that you need to be careful with how you tune each half of the airflow model. If the MAF is still active and not failed right and if the fuel trims are changing stuff on the fly, it can and will throw your data off.

Getting your wideband wired into the computer is going to streamline everything. I wouldn't even bother doing the MAF curve without first going back over the VE using the wideband error. Then do the MAF once the VE is complete.

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Thanks for the suggestion 5FDP. I'll read up on pinning the wide band in and run back through VE. The learning curve has been steep, but I love the process. More questions to come.

Yes, beta software. Should I go back a version?