83 Gman

Hi
I've been reading and most RPM surging at idle or just off of idle deal with either IAC or a vacuum leak.
The TPI that's on my engine was from someones else's build.
It's a speed density system.
It came from an 86(?) 305 Camaro engine.
I plugged off the 9th injector port and installed 3rd design 22lb Bosch injectors from South Bay.
When I installed it I made sure the TPS and base idle speed was set correct and there are no vacuum leaks.
It is also EGR delete.
Base timing is 6*.
All said and done the idle is not smooth when hot and off idle at 1200 there is a "surge".
What I mean by this is, at operating temperature, it runs good for a short time then starts to run uneven like the mixture was getting lean then run's good again.
There are no codes.
I have an adjustable fuel pressure regulator and it's set at 40 PSI with the engine running.
Using a scanner are there any values I should look at to diagnose this problem?
I will go back and retrace my earlier steps if need be.
I'm also using a Dynamic ELB tune.
Thanks