I am having some very strange lean issues and I have tried just about everything to no avail. The setup is an LS3 525hp crate engine. You would think that you could put a stock LS3 tune or even THE GM tune for this 525hp crate engine and it would at least run decent after idle changes, but instead, the fuel trims have been massively off. I found some cammed LS3 tune files with similar cam specs online and they required way less airflow on the maf calibration than what I had to add. When you rev from idle, you can watch the wideband peg lean. This happens in most transient conditions. At WOT, the vehicle went dead lean (wideband pegged) and my Lambda error was showing 51% error and I still had to add more the next time. Something just does not seem right. I am running MAF only currently. I will attach the tune and several logs.

Pay attention to the LS3 idle 2 log when it first fires up, the wideband is pegged lean (1.29 lambda) and you can audibly hear the vehicle running lean at this point, but the second the fuel trims come online, they only correct it 5 ish percent but it puts the afr at stoich.

LS3 525hp MAF idle part throttle new.hpt
OL log 1.hpl
LS3 new.hpl
LS3 idle 2.hpl

P.s. on the LS3 new log, ignore lambda error, as the wideband stopped reading during the log.