Hey so I have a D15b as of right now in my 2000 Civic coupe EX, I plan on dropping a b20b from a CRV into my car however I’m confused what ECU or Wiring Harness I will need. My plans are to have a B20b low comp block, b16a2 high comp cylinder head, and an LS Transmission. But can someone please help me out by telling me if I’m able to use the same ECU and get a b20b wiring harness or what? Thanks!

 

What ecu?

 

• The wiring harness you currently have will be fine.
• NO the ecu you currently have should not be used for the B20 Vtec setup.
• I suggest a chipped OBD1 ecu and OBD2b to OBD1 ECU conversion harness
• Make sure the chip provider installs a tune on the chip that matches your setup (you will eventually want an actual tune though.)
• Enjoy and have fun.

If your going to rock the B20B for a while until you get the funds for the VTEC head...

• The wiring harness you currently have will be fine, just that some plugs will go unused like the vtec harness etc.
• NO the ecu you currently have should not be used for the B20B.
• I suggest a P75 OBD2B ECU from 99-00 Integra, no conversion harness needed it will be plug-and-play
• Enjoy and have fun.

Oops, I confused the JDM B20B for the USDM B20Z in my B20B suggestion above...
The JDM B20B engine I believe is missing the crank position sensor, and maybe some others too that a USDM OBD2 ecu like the P75 would look for.
That being the case, you can probably run an OBD1 94-95 Integra ECU and an OBD2B to OBD1 conversion harness and be fine.