bigg86

i just finished rebuilding my B18 and for some reason it wont rev past 4500-5krpms and if it does then the engine dies and shuts off. I cant downshift either or the same thing will happen... But i noticed when im in the freeway in 5th gear the car will drive just fine till about 5500rpms. i havent taken it past that tho...

Here are my mods:
84mm wiseco pistons
eagle rods
darton sleeves
micropolished n balanced crackshaft
inline four crack pulley

Extreme P & P head
brian crower stage 2 boost cams
brian crower dual springs + retainers
1mm oversized valves w/3 angle valve job
STR cam gears

sk2 intake manifold
sk2 70mm throttle body
3 bar map sensor

255lph walbro fuel pump
automotive fuel filter
automotive FPR
automotive fuel gauge
AEM fuel rail
275cc injectors (no boost yet)

external msd coil
MSD 6AL ignition box
apexi neo fmu (upgrading to s300 once i start boosting)

ram exhaust manifold
44mm tial wastegate
T4 custom turbo
3inch downpipe
3inch cat back
31x12x3 front mount

I only have about 200 miles in it since i rebuilt it and ive been driving it slow with no boost, but i noticed the other day that the car started holding back once it past 4kprms..... i really dont have any ideas at the moment of what it could be.... if you guys have any ideas or if anything like it happened to you, please let me know.... Thanks!