Here some info on my 97 CIVIC EX.....

-99 SI motor B16A2
-97 GSR Tranny
-96-98 GSR ecu
-Right now my car still using 96-98 ecu harness..

Has DC 4-1 header, Tanabe cat-back, AEM cai and AEM fuel regulator. Right now the car is very slow.... can it be the GSR ecu effect the performance?

I wanted to convert it back to OBD1 with the adaptor OBD II to OBD l. But can I use a JDM p73 JUN programmed ECU with the adaptor just plug and play or JDM and USDM ecu's are different? And will not plug into the OBD I adaptor? Since my motor is stock can I use the JUN programmed ecu? Can it harm the engine? please let me know ........thanks for your reply.....

 

a JDM ECM will plug in, but you have to make sure you get an OBD-IIA(96-98) ECM, since the 99-00 ones are OBD-IIB and have slightly different plugs. If I were you, rather than spending money on some generic "performance" ROM from Jun or Spoon or whatever that should work well, I would get an OBD-II>OBD-I adapter harness, an OBD-I ECM, and run a Hondata S100 that you can have tuned for your specific application.

 

Thanks inspyral for you reply..... its hard to find 96-98 OBD II P30 ecu... all I can find is OBD I P30 ecus... Since the JUN P73 ITR ecu is almost the same price as a stock P73 or P30 ecu.....Does the ITR ecu have similar vtec point and mapping as P30 ecu? please let me know why stock or lightly would do a better job...

my plan is to get ITR throttle body, Intake manifold, soon and later on ITR or SI tranny....b/c the gsr gears are toooo long...

 

I would expect an ITR ECM to have at least slightly different fuel/timing maps, as well as VTEC engagement point, given its higher redline.