im swapping 00 integra r engine into 99 civic si. i use the civic wiring harness as well as the si ecu correct? I don't use the jdm ecu that came with the engine.
just trying to cover my bases. thanks

 

Yes, use the 99 Si engine harness, and don't forget to either change the IAT plug/extend the harness, or use the Si intake tube and IAT.. Also, use the Si ecu temporarily, and then if the R ecu is a JDM version, you can get an OBD2b-2a ecu adapter and then use that ecu..