I have a 99 civic si that I bought with a knocking motor. Had a friend pull the motor and drop in a 96 b18b1 I had laying around. It's running on an OBD1 dizzy, and OBD1 p75 ecu with jumper harness. It seems like between 2k-3.5k rpm, it loses power, its jumpy, and it backfires randomly, but only after it has warmed up. No CEL codes, no maintenance required light. Changed spark plugs, tried a different distributor and wires, put some seafoam in the gas. No luck. Can anyone help me diagnose or solve this issue?

 

bump

 

confirmed your cel light works?