Stumble under boost... help!!
 

I've tried searching, and I have tried everything I can think of. About 2 weeks ago my car flooded. After doing deflood and changing spark plugs the car had issues. As soon as the car hits about 5 psi of boost it stumbles really bad and backfires, just falls flat on its face. RPM doesn't matter, just boost pressure. Does anyone have any ideas?

Mods:
Intake
Non-seq turbos
Full Exhaust
Apex'i SAFC

All mods were on the car when i bought it and I am saving towards a PFC. The car ran and boosted fine before it flooded and nothing else has changed. Please help me. I am at wits end.

Thanks

Whatever caused it to flood may also be causing it to stumble rich. I would triple check the SAFC setup. Also make sure the MAP sensor vacuum line is connected properly and there are no leaks in the path between it and the manifold.

I think what caused it to flood was a very cold night and the fast idle stuff is disconnected. It started and idled but shortly died and wouldn't restart. Nothing has changed on the SAFC since before it flooded.
The MAP vacuum line looks fine and is connected on both ends. I have checked my intake to see if i have a crack in a hose that opens up under boost but can't find anything.
Could a bad or dirty ground cause this?

I don't think it is a ground problem and it doesn't sound like a boost leak. You're either getting too much fuel, too little fuel, or having ignition problems. Based on what you said I believe it's too much fuel. At this point I would use a wideband to determine exactly what you are dealing with. Otherwise you are throwing darts in the dark.

I have a wideband on the way so I will see what happens when it gets here. Thanks for the input. Any other ideas are still greatly appreciated though.