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Fuel Trim Issues

Hey Yall,

Over the past couple of weeks I have been struggling to find my solution to a really high LTFT/STFT reading. After installing the Big Boost Stage 3 turbo kit (I know, I know), my LTFT's spiked to 25% at idle, but drop to 0-3% while accelerating. I have sealed the downpipe connection perfectly, found no un-metered air entering the system, replaced injectors and HPFP with an XDI35 pump and 30% double sealed injectors, MAP, TIP, MAF, upstream O2 sensor have all been replaced. I pressure tested the whole system, and found no boost leaks. I have gone as far as re-routing my catch can lines, replacing the EVAP harness to 2014-2015 specs, and brake booster vacuum pump. I am at a complete loss, and it is only making it a hassle to get my car tuned. Any ideas?