if anyone can help i have a 91 awd auto with a fresh eng rebuild (mostly stock just bored .020 over), a walbro 255, and a new 14b. i was getting what i think was fuel cut between 2500 and 3200 RPM's unless i really feathered it. i dont have an mbc but i'm going to make a homemade one just so i can turn it down. but anyways i tried replacing the inj. with used stock 5spds (450's) but it turned out the car wouldn't hardly run is there a chance that i'm getting to much fuel and just need a fpr and afc? i really don't have the money for any of that yet i just want it to be a daily driver at least for a couple more months. ps anybody remotely close to mchenry county i would love someone to take a look and give me an educated decision on what to do because i'm stumped.

Its not fuel cut. You can't push through fuel cut. What you probably have is boost leaks that are causing your A/F to become very rich. Check for leaks in your intake piping and see what that comes up with.

Also, double check your plug gaps, and make sure your wires aren't arcing. If you do hit fuel cut, it will likely be at higher rpms than you described, and it feels like you ran into an imaginary wall, not just missing.

give a description of your symptoms.

Not sure where to start here:

A MBC won't let you turn the boost down any further than the wastegate. If you want to run low boost, just hook up a boost source directly to the wastegate. That's as low as you can go.

Fuel cut: Isn't really from not enough fuel. It's the ECU seeing too much airflow, freaking out and then cutting you off.

Injectors: Running 450cc injectors on an auto ECU is going to be a bad idea. Bascily the ECU will fire them just like your stock injectors but you'll end up dumiping ~15% more fuel and drowning things out.

Best bet is going to be to test for intake/boost leaks and then log the car.