07 Z06 WOT AFR going rich after 5500, log attached

[Gpargament]

2007 ls7 Z06, My issue might be mechanical, but before I start replacing parts I wanted to double check the tune, and also ask the advice of the advanced and master tuners who might have seen this before, any recommendations where you would start if it is mechanical?

Mods: Speed density, 230/250 660/660 cam, heads are built 685 dual springs, chromoly push rods etc... hurricane intake, 1 7/8" headers and full exhaust no cats.

issue: as you will see in the log, after 5500 rpm my AFR just starts plummeting towards 11 flat. Car runs amazingly fast though, the run i attached had less than a degree of spark and I have lowered it since so there is no more knock. I have double checked the wideband with another, one in the exhaust and one in the tailpipe, readings almost identical. no surging or bucking, and it pulls hard all the way to 7k, but according to the log its fckd up... very confusing

possible issues/causes:
1) cam intake duration could be too small, and there is simply not a large enough duration on the intake side to acquire the necessary air, maybe I should have gone 240/250. The COPO ls7 uses a 238 27x and made massive horsepower, 7 or 800 plus, so i thought my specs should be ok.

2) no catch can, oil could get recycled into the intake, causing the fuel mixture to be off, and not getting complete combustion at high rpms

3) stock TB and intake manifold aren't up for the task, might need the 102 tb and intake, literally not enough air.

4) I could rape the VE table and drop almost 20% from 5500-7200 but that shape looks terrible for a WOT table, every other car I tune steadily adds fuel as rpms climb, or at least holds stagnant, i have never seen a car make this shape ^ in the wot area

5) I just messed the tune up and that happens

All recommendations are appreciated from both the tuning side and the mechanical side. Thank you in advance.

WOT cant hold 12.7.hpl
min af 60 with ve.hpt

[ahmedabri97]

You are restricted by the stock intake and throttle body just decrease some airflow from 5200-7000 rpm until the afr goes to commanded.
Every setup differs from other when tuning VE or maf just go with what the engine wants.

[Gpargament]

Awesome, thank you, we had snow in Colorado yesterday, as soon as it is dry. I will adjust, log and post results... very much appreciated

[lukearmstrong1990]

the engine being 7.0 with that size cam which I assume is on 112LSA is behaving normally. it wouldn't be as severe with a bigger LSA like 114/115

its past its peak torque on longer requires the same fuel mass.

edit the VE tables and remove fuel proportionally from 5500-7000rpm to maintain your target AFR. its normal to see the VE table data fall away after peak torque to rpm limit.

[Gpargament]

I never updated after your help and i enjoy closure lol. I did change the spark plugs, my iridium 6 heat were about .043 gap i picked up the cheap copper vpower ngk heat range 6 gapped at .038 now afr holds till 6400 before i need to pull gas because it goes rich. I just ordered the ecs supercharger, as soon as it is installed I'll update the results. But you are all correct, my air intake is limited, hence i went forced induction lol