Misfire, runs rich at 2500 rpms. Need help asap

[PlanZero]

As discussed in my other thread, I just did my motor swap, now car is running rich. Before the motor went, the car was running perfect.
Idles fine, but at 2500rpms starts to sound like a misfire and sputter, black smoke I didn't push her past that.
Checked the following: BLT, plugs and wires are new, compression is good. Rechecked timing three times. All plugs and connections are good. Swapped 02 sensors.The only thing I'm uncertain about is the CAS (stock 2ga)which I'm checking tomorrow, but I thought a bad CAS would show symptoms other than only at 2500rpms.

 

[jakk220]

Is this happening while driving or revving the engine in neutral?

 

[PlanZero]

Is this happening while driving or revving the engine in neutral?

Only under load, right as the tubos spooling up. After a short test drive the brand new plugs (gapped at .028)were black with carbon. No CEL and no logger.

 

[jakk220]

Faulty fuel pressure regulator? If its all the plugs that would be my first guess at a culprit

 

[jakk220]

Did you check the ECU for any leaky caps?

 

[PlanZero]

The ecu was fine last time I checked it a few months ago. The car was running perfectly fine but spun a rod bearing so we dropped this built motor in.
I believe the fpr is from the old engine, as is the intake manifold, fuel rail and all sensors. I'll double check tomorrow. I have a feeling we're just overlooking something or I connected something wrong on the harness.

 

[jakk220]

just take it off and try to blow through it. If you can then you know its bad. Throwing any CEL's?

 

[jakk220]

Make sure your MAF is plugged in and not bad. I had forgot to plug mine in once and had this issue.

 

[PlanZero]

Well today I checked and retightened a few things, took her for a ride and she felt great. Then, when I went to leave my buddy's an hour later she wouldn't start. I was able to get a code for the cas, which was my original suspect. Going to put a 1g cas on tomorrow. I have a question about the rewire which I will address in a different thread.