2016 lt1 swap way rich

[bonesv8]

HI,
I have done a 2016 lt1/8l90e swap in a 66 chevelle. The motor and trans are stock with holley exhaust manifolds. it has a retro tanks and zl1 fuel pump in tank.
my problem when it switches to closed loop the ltft drops to -30% while the o2s are staying in the leaner area. it has a new maf, map, hpfp, oxygen sensors are new but not a factory sensor.
the tcm and ccm are new (with a gm dealer tune). the reason so many new parts is the drop out was from a wrecked donor.
I am also seeing -4 timing at idle. I am at a loss on what is causing this. the car struggles to runs and when in gear just crawls. watching the scanner the fuel rail pressure sensor reads 2000 psi at idle and then drops pressure as I am able to rev it.
The tune is factory with vats and other emission codes tuned off, but some still come back when scanning for codes.
here is my tune and log file. 3/4 way through the log file I reset the fuel trims.
Thanks for any help

[tunerpro]

Are you using the factory airbox ?

[bonesv8]

No.
4" pipe, maf 11" from tb. (According to GM lt1 crate motor install)
Pcv vents are hooked up between tb and maf

[Mep_q8]

Please log Torque Source and type.

Do you have a wideband to confirm the factory O2 sensors are reading lean? The Long Terms pull fueling down to -30% and you're Short Terms start oscilating between 0% - 5%. Seems like they are doing what they're supposed to be correctly.

Either way give this a write and see how it reacts.

[tunerpro]

No.
4" pipe, maf 11" from tb. (According to GM lt1 crate motor install)
Pcv vents are hooked up between tb and maf

What do your trims do with the MAF unplugged?

[bonesv8]

Mep_q8
Thanks for the tune. I am sorry, I am unsure on what torque source and type are.
I do have a wide band I can try, but I am going to try a set of factory o2s first.

tunerpro
I have tried to run it with the maf unplugged, it runs worse and I can barley keep it running long enough to scan it.

[bonesv8]

Long story short I installed factory 02 which made a minor difference. I leaned it out by 28 percent, motor runs and sounds good, fuel trims are good.
But trying to drive the car it won't go over 30 percent throttle like in limp mode. I don't have a bcm with this set up. I have read that it is needed with these 8l90e transmissions. Can any one confirm or deny this.
I don't have a bpp sensor just 12v coming out of the brake switch to the ecm when applied.

[tunerpro]

Glad to hear its running better now.

There are GM performance kits that use the 8L90 without the BCM, so I don't think that's the issue. Does it set any codes when it goes into limp mode?

[bonesv8]

Just u codes for no comm with ebcm and bcm