hi i have an ef hatch with an obd2 b16 going in what wiring harness do i buy looking at rywire but not sure if obd1 or obd2

 

You need your stock harness, obd1 ecu jumper (or obd0 b16 ecu), and an obd2 engine harness (for misc connectors)

 

The Rywire harness you buy depends solely on what ECU you plan to run.
OBD1 ECU = OBD1 jumper
OBD2 ECU = OBD2 jumper

 

So my stock harness is necessary?

 

100% needed.

There is a cabin harness and an engine harness that, when combined, make a path for wires to go from the ECU to the appropriate sensor on the engine.
A different engine harness does not match up to the cabin harness.

The jumper harness you get from RyWire (and other places) reroutes the wires from the cabin harness to the correct location on the new ECU.

 

Alright cool thanks i have cabin harness not stock motor one i can probally find one

 

It would also help if you mention whether or not your car is a dpfi or mpfi.

 

^^ there he is! pnapoliano - before you shell out money to the big name manufactures, have a talk with 'CRX Si-R'.
Zero disappointment!

 

Check out my instagram c_zapien for pics or a dpfi to obd1 set up I am making. Started this on monday.