Frustrated - LS swap cuts power on WOT

[Lexuswrench]

I have a 5.3 swapped into a G35.
stock block
4.8 flattop pistons
706 heads ported
texas speed 224r cam
sheet metal intake with 102mm DBC throttle body
decapped gm flex fuel truck injectors (flow tested)
speed density tuning

First off, the car idles perfect and drives well at low throttle and will cruise around just fine. If you very slowly roll on throttle it will allow you to give it more throttle but as soon as you get to high rpm or WOT, especially when you stomp it, it cuts off as if you're hitting the brakes and bogs down.
I have tried all sorts of vm table modifications, as well as timing. No matter how much timing I pull, or how much fuel I add, it still knocks and cuts power when getting on throttle. I have also checked fuel pressure and it drops from 58psi to 50psi under throttle, but I cant imagine that would cut ALL power instantly. Nothing seems to change this. I have posted one of my logs below. I also changed the car to E85 to see if it stopped the knock, but it still has knock and the same issue persists. Any ideas?

5-18 run 1.hpl

[5FDP]

Post the tune.

Fueling still needs a ton of help, the fuel trims are lean just about everywhere. Lots of times at +20 to +25%.

Do you have a wideband hooked up?

[2xLS1]

Fix the FP drop. #1 problem I see with EFI swaps is fuel delivery. There is a reason OEM fuel systems are designed as good as they are. And generally decapped injectors are junk.

[SultanHassanMasTuning]

posting the tune also helps

[Lexuswrench]

Post the tune.

Fueling still needs a ton of help, the fuel trims are lean just about everywhere. Lots of times at +20 to +25%.

Do you have a wideband hooked up?

I do have a wideband hooked up, its clear that even when the histogram shows im not lean at all, it still cuts out. I just ran to the gas station and will post that log + my tune along with a screenshot of the wideband. It seemed that it was pulling okay up until about 70% throttle when I roll into it and then would cut out. Also about the fuel trims, when the car actually cuts out during higher TPS they seem to be level or at least not too far off. Whats odd to me is that often times it will cut with zero KR, a decent WB reading, and not that aggressive timing. Still have to fix the fuel pressure issue though.

gasstationrun.hpl
latesttunehp.hpt
wbscreenshot.PNG

[SultanHassanMasTuning]

in your VE no way to need over 105

something is wrong

the injectors in the tune is over 80lbs

SD setup is not correct

[5FDP]

Yeah, that tune is all sorts of wrong.

The MAF isn't failed right. Needs to be 0hz on the MAF fail high and the 3 DTC's need to be MIL on first error.

You put in decapped injectors but changed a bunch of other injector data settings that you have no real clue if that information is right. That is the problem with decaps. The offset data is changed a ton but only thing you know is that the injectors flow more because you have them flow tested.


Cylinder volume for a 5.3 is .66594 and not .68749.

Tahoes never came with a manual either, just leave the transmission drop down as a 4L60e and have all that other stuff disabled.

Get better injectors and fix your fuel pressure issue. Start tuning the VE table in open loop with zero fuel trims and closed loop function.

And lower the PE enable to 65% and lower the commanded AFR in PE to something like 1.200 while you fix things.