R33 Boost Cutoff

[Phil R33]

Hey guys only new here, hopefully someone here is able to help me out..

Ok so i have a 1994 r33 gtst series 1 skyline, 144 xxx kms, Its stock engine wise with only the basics done to it, coilovers, rims, strut brace, sound system, steering wheel and the mandatory stickers haha, its got a 2.5 inch exhaust with hiflow cat and a cannon, so shes pretty basic but still looks the goods.

Anyways now to the problem, As your driving along and you start to lay into it, ie drifting, draging or racing, as soon as you hit 4500 rpm it starts spluttering and carrying on, it will still produce power, and still gains speed and it sounds terrible, it does this through all gears and maxes out at about 170, although through the coughing you can get it to 180.

Ive been told its a few things these include, fuel pump, leads, spark plugs, coilpacks, air meter sensor, boost leak, an electronic limiter to stop people winding up the boost and blowing their stock turbo.

When i bought it, it came with the typical pod filter, im not the biggest fan of them mainly because their a defect, also because their sucking in hot engine bay air, and also because i fing the "sucking" noise they make annoying, so last week i replaced it with an airbox and a fresh filter, i also noticed this has helper the spluttering a little although its still quite noticable.

It also does this no matter how much fuel it has in it.

Basically im reluctant to spend any money on it until i can be convinced what it is, so if anyone knows the answer or has had a similar issue please feel free to help me out, cheers guys, Phil

[Hadouken]

coil packs, plug gaps

[Got a Pulsar]

This^^^

or

Dirty / faulty Airflow Meter

Too much Boost. R&R

[666DAN]

4500 rpm is when the solenoid for the actuator on the turbo goes from low to high boost.....if there is a bleed valve or dodgy actuator line it could be boosting too high.