I have a 96 Civic with a B18B1 swap. At around 2500 to 3000 rpms the motor falls on its face and starts sputtering. If you put your foot to the floor it will wake up and take off like a bat out of hell.
Now I have replaced the O2 sensors before the cat. because of high voltage readings (CEL) plus I have done a tune up (Plugs - wires - cap and rotor). The tune up took care of the problem for a while but it came back.
I have talked to the techs at Honda and got no answer. I have searched on the net to see if someone has ran into this problem (they have) but nobody can seem to come up with a fix. I have no CEL at this time but the problem remains.

1999 B18B1 original ECU and trans swapped into a 1997 Civic EX with EX fuel pump and with B18B FPR.

Any ideas please let me know.

Thanks