car is running like shyt after boosting. it runs like its in limp mode.

1987 rx7 turbo II
mods we did are greddy 25g turbo (i think) with greddy type c wastgate,s5 intake manifolds with s4 throttle body, rtek 1.8, 720 prim and secondaries, re-amimeya twin plate clutch and flywheel, eliminated the omp ,xs replica blow off valve, bigger top mount.

so whats happening is when you rev it high and it starts to boost it backfires then goes into limp mode and then after that runs like shyt. at first we thought it was cause there was no gas, and there wasn't, so we put gas in it and it ran perfect again. but then wen u rev it high yet again it goes into **** mode. friend is about ready to give up on the car cause we cant figure it out. so any help is needed.

here's a little crappy video i shot wit my phone( also theres a loud annoying whistling noise coming from the flywheel clutch area it does it both when u press and unpress the clutch pedal and only does it past 3000 rpm)

http://s77.photobucket.com/albums/j5...t=MOV-0030.flv

 

anyone have any ideas? im also helping with this car.

 

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