Help feels like a early fuel cut

I have a 90 Integra with a b17 gsr converted to obd1 including injectors and chipped po6 ecu that’s converted to vtec chip was done by basic modifications like intake header exhaust and the car has been fine until this year and I have had this issue all year and what happens is if I’m driving normal and decide to stab the gas the rpm start going crazy after 4000 rpm and it feels like it’s in fuel cut and If I easy into it no issues the vtec is set at 4500 and redline is set at 8200 rpm now I’ve check my timing both mechanical and ignition and swapped ECU with know good ECU and checked tps voltage both closed throttle and wide and made sure there are no dead spots. I’ve gone through countless distributors and now have a oem distributor which is known good fuel pressure is at 50psi I have been leaning to it being a tps related issue and replaced the throttle body with a oem one with the tps untouched and I still have the problem help me figure this out so I can enjoy the car again

Have you checked the MAP sensor?

I had a similar issue, I’ll try and dig through some of my things and see what it was for sure.

Thanks I ordered a new map sensor yesterday to see what it does

This sounds very much like a dead fuel injector. Use a stethoscope/Long screwdriver and listen to each injector for an audible clicking or remove and have them bench tested.