B20-B in 91 integra

[onyx22]

I'm driving a 1991 Acura integra with a B-20 OBD 2 motor, still using stock PR4 ecu, I'm also still using the stock integra intake manifold so that the OBD-2 motor would link up to my OBD-0 harness. It is very sluggish almost like the timing was off but, cam timing was never altered due to the fact that its a bone stock CRV B-20. What else would be causing this problem??? I tried turning the distributor but, it doesn't make a difference no matter what way I turn it, that is also the stock integra distributor. A friend told me that an APEXI S-AFC might be able to see and cure the problem, am I even able to use that with my year integra??? Could fuel be an issue. Any help or advise would be greatly appriciated ??????????