MCSMASHING

Hello everybody, I’m running a LQ9 with a carburetor set up. Details below. I had to rebuild my transmission and replace engine oil pan, due to going DUKES OF HAZARDS. I pulled the engine to reseal engine, removed heads and changed the gaskets. That’s as far as it goes. No engine rebuilt.
I went with a higher stall nothing to crazy, roughly 2200. “Upgraded” all internals of my 700r4. No lock up. Need to fine tune governor, shifts way too late. It’s a real legit built 700r4, no problem so far.
Anyways the problem occurred after the reassembly of the power train. At first it was fine. Down the line, a few months later, after start up and a little warm up, I would start to drive, and it would seem that the transmission would hesitate to shift(governor pressure) the engine would start to bog and backfire, and sometimes would stay on with no power and bog the whole time. Any acceleration would not result in any improvement, maybe more backfires. Shut engine off, restart engine ran fine for a little bit and back at it again. Over time seems to get worse. By the way only during acceleration while under load. Neutral or park, engine revs fine.
Though maybe a carburetor problem, so I bought a new Edelbrock AVS2 650cfm. nope same problem. Previously had a Quick Fuel 750cfm, basically a Holley four barrel. I run it pretty lean due to high rpm idle. Right now limit screws turn all the way in for edelbrock carb. Also noticed fuel pressure was at 3psi running.
I know I have exhaust leak due to no header gasket and 2 inch hole on cylinder 2 primary tube, which I patched with some jb weld a beer can and some clamps.
After the initial start up and warm up, car runs “fine”as far as the problem I described. At first I thought I might have too with a bent valve, damaged msd box(3rd one now), brake booster or air leak. What do you guys think? What should I do to further diagnose, or is it so simple that I’m over looking something. Please help, any input is greatly appreciated, thanks for reading.
LQ9 stick as far as I could tell
Edelbrock rpm performer intake
Edelbrock AVS2 650cfm
Holley Blue Electric Fuel pump
Some long tube headers
MSD 6014 Ignition Box TRUCK H.O.
700r4 “built” 2200 stall no lock up
2.73 ring gear

LQ9 Carburetor Conversion

Header primary tube with hole fixed