Sputering at 5k

[cman3000]

Just got my new 1g, and after driving it for 15 mins, it sputtered under boost at around 4k. Thought it was overheating, as there was no intake going to the turbo, just a screen over the inlet. Got an intake today, but it is still doing it, seems a little better but not much. Car runs great when cold, no problems. Water temp is around 205 after driving for a while. Any ideas? Here is my engine setup:

Balanced Crankshaft
ARP Main Studs
Eagle H-Beam Rods
Weisco 8.5 to 1 compression heat coated pistons
New High Volume Oil Pump
All new timing components. (pulleys, tensioner, etc.)
Unorthodox Underdrive Lightweight one piece Racing Pulley
Resurfaced block
Bored over and honed cylinder walls
Balance Shafts removed
1mm Oversized Stainless Steel Valves
Bronze Valve Guides
Lightly Ported and Polished
Web 546/547 Street Grind Cams
Power Enterprise Kevlar Timing Belt
ARP Head Studs
Cosmetic Multi Layer metal Head Gasket
3" Stainless Steel Turbo Back Megan Racing Exhaust
2.5" Victory Performance Stainless Steel O2 Housing
Tial 40mm Waste Gate
Supra TT Fuel Pump
Re-wire fuel pump relay
8an braided fuel feed line from tank to fuel rail
K&N billet 8an fuel filter
SX Adjustable Fuel Pressure Regulator
780cc Fuel Clinic Fuel Injectors
MAF Translator 3" GM MAFS
Bullseye T04B 50 Trim turbo (oil & water cooled, -10an oil drain)
Aluminum High Performance sheet metal Intake Manifold
2.5" Aluminum Intercooler piping
Tial 50mm BOV
2nd Gen Polished Throttle Body Elbow
32" x 8" x 3.5" Front Mount Intercooler
Alumium Mishimoto Radiator Slim Fans (One Puller & One Pusher)
New Water Pump
New Hoses Braided
6an turbo coolant feed and return line
New Battery
New Alternator
New Coil Packs
New Ignition Module
New Spark Plug Wires and Plugs(BPR7ES)
EPROM ECU with Keydiver Chip reprogrammed for the following; 8000 Rev Limiter NO Airflow CAP No Fuelcut Octane Reset Shift CE Light @ 7000 RPM Enhanced closed loop MAPS Knocksum Gauge 780cc injectors/264us deadtime 3” GM MAFT 850 RPM Idle 45 PSI AFPR 11.0:1 WOT A/F FED/AWD Locked Baro & Airtemp

Sorry the list is long, but i just want to make sure i dont miss anything that might help diagnose the problem. Thanks for the help.