Sr20 1/4 throttle response. Someone please help!!!!

[drftr68]

Ive been dealin with this problem for a while and ive tested pretty much everything i can. I really need help. The problem is that i can only give the car 1/4 throttle beforw it started spitting and sputtering no matter if im in boost or not. At idle i can hear it missing a lil too. Heres a list pf wat ive tested and replaced:
Maf sensor-voltage and signal going to ecu
Cam sensor-voltage and signal to ecu
All injector signal wires to ecu and resistance on injectors1,2,4 read 11.1-inj 3 reads 15.8
Checked coilpacks and signal to ecu*
Checked tps signal*
Checked fuel pressure-43 psi
Checked timing- 15* at tdc*
Checked vaccum lines and piping
Replaced:
Knock sensor
Headgasket
Turbo
Vaccum lines
Spark plugs
Tps
Maf
Ecu
Replaced coilpacks
Cylinder leakdown test
any sr gurus would be greatly appreciated ill take any advise and use it. Ive done everything short of replacing the wiring harness.