300zx Strong Cut

[Sam91TT]

Hello guys, im new to the forum.. Anyway i have a problem on my Z that's been for over a year or so.. i really appreciate if someone would help..
So sometimes when i hit full boost and hi revs 5000+ the engine completely cuts and it starts again when the engine drop under around 3000 rpm sputters for around 10 seconds, so i keep on revving it although its sputtering and then everything goes back to normal.. P.S if i don't rev it when the cut appears the rpm just drops and the car dies.
Additional info.. all cylindars are firing..
I am really pissed and i miss driving it without having this issue !
Any help would me appreciated..
Yet more info is that it used to do it alot less before i had my ecu socketed,chipped and boosted to 14psi.
I guess the additional power made some stress on this malfunctioning "thing"
i checked the ECU and code 55 all things are normal