Help! Weird Stuttering only at WOT in 1st Gear

Alright guys I'm pulling my hair out trying to make WOT work in first gear without stutters/hesitations.

For context I have a 2017 Dodge Charger Pursuit 5.7 AWD that I have upgraded after having an MDS lifter collapse. I put in new Non-MDS Lifters, new Manley 2640 Pushrods, Mopar Performance Springs, JBA shorties, a 6.4 Intake with an MMX SRV kit, and a 6.4 Non-MDS Camshaft. I had never tuned a car before so I started by doing a basic NN tune using a wideband (installed on the left header) and adjusting injector mass, then went to Closed Loop VE/Speed Density, then Open VE/Speed Density, and am now doing the real HP Tuners AI based NN tuning to try it out. All that said, LTFTs are below +-2 with NN back on and the car feels dialed...except at WOT in first gear.

Ever since starting the car after the rebuild, seemingly irrelevant of tune, when I go through WOT in first gear I have 3-5 flat spots in the RPM curve where the engine seems to fall over, and the 0-60 is about half a second slower than before the rebuild (5.8 back to back vs 5.2 back to back). This only seems to happen in first gear. If I do a 30-70 mph rip in 2nd I seem to have no or very limited issues and it pulls almost cleanly. The hesitation happens around 3200 RPM, 4600 RPM and 5550 RPM as the main culprits. I have attached logs of runs with a screenshot of the data I pulled from them and a log of a higher speed run in 2nd gear. I have a lot of data so let me know if you need more.

Does anybody have any idea what is going on?
The only issue I know of right now is that cylinder number 8 has an exhaust gasket manifold leak, but that will get fixed next weekend. I have also seen up to -0.5 of a degree of knock retard at 5500 rpm on one or two of the pulls due to high IATs, but nothing consistent. I have tried isolating the trans, spark, knock, fuel injectors, and everything else I can via logs and I don't see any dips or consistent coinciding changes in knock or spark or anything besides TC Slip during these events. I could really use some help.

What else should I try to log or specifically look for when I get to work on the car next weekend?

Edit: Figured it might be important to add that I'm targeting .85 Lambda (~12 AFR E10) at WOT. Also thinking back on it, the car seemed to both make less power but stutter less when it was excessively rich like when I had first started to try to do open loop tuning. The car was idling around 12 AFR and dropping to 11-11.5 the WOT pulls were smoother, but slower. IATs were also about 10-15 degrees lower that day, around 80-90. Most of my tuning has been around IATs of 100-105.

still looking through it, but the VE tables don't look good and is an area i would focus on improving.

For what it's worth in closed loop my short-term fuel trims are all under 3% and in neural network with those VE tables, my long-term and short-term fuel trims are under 2%. I don't know if all the VE values are high because the injector mass got changed at the beginning but that's what I've been assuming. Is that what you're talking about needing major improvement?

If If having major injector value changes before going into open loop is a sin and I need to redo the open loop tuning with the injector values set to stock, I can totally do that. I'm an absolute newbie here with a lot of time and patience.

I'm planning to install a wideband in the right bank and fix the exhaust leak this weekend, so hopefully that should give me more clues.


Edit from the future: My VE tables were super messed up due to me not filtering transient fuel data, and due to improper injector scaling

Going to update for everybody. I was able to correlate 95% of the issue with a failing torque converter clutch and terrible stock lockup settings in 1st gear. The other 5% was the right bank running about 4% off in terms of fueling compared to the left bank. The car is now running a 3600 stall and torching all 4 tires on launch. Life is good!

I also reset the injector values to stock and fully retuned the VE on open loop based on the new values. I then took that tuned open loop setup and put it into the NN tuner. I dialed in the last few items by tuning the VE for WOT (car still runs open loop for WOT even with NN on - people seem to debate this but I've confirmed it through testing) and the NN values for part throttle fueling. The car runs like stock until you get over 60% throttle now.

Here is the tuned file it's running now. Hopefully this will help those of you with a similar setup.Attachment 152788

Quote:

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Originally Posted by STRAIKER

help those of you with a similar setup.

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there are millions of 2015+ 4x4 chargers

with stock 5.7 liter hemi

and 3600 stall

and a nag 1

: )

My engine setup is pretty common. A 5.7 rocking a basic 6.4 cam kit and bolt-ons was in 4 or 5 common tuning threads. It's how i got started!

You're right though, everything else about the car is absolutely sick and pretty unique!

AbsolutelySick

what a great user name!

enjoy your tire roasting monster

bet its fun : )