I have a 99 Civic SI(mods listed below) and I am wondering if an ITR ECU would make my car gain anything. I know that the rev limiter and fuel is different than a SI ECU. The new ITR's have the fuel shut off w/ the chipped key, so I was wanting to know if the older ECU(like the 98) would work with my car and if it would help gain or lose any horsepower? If it would help me does anyone know where I could find one and about how much? Thanks in advance.

 

The 1997/1998 ECUs will not work in a 1999+ Si. Pinouts are completely different. You could spend $200+ to buy a OBDIIv1 to v2 harness to get it to work, but I am not sure why you would bother.

 

Exactly, if you want a 96 Spec ITR ecu (JDM) or a 98 Spec ITR ecu, you'll need to cough up an extra $200 to get the converter harness so it'll all plug up correctly.

Fug that!

Get an OBDI ecu, reprogram it with a Kenji program (he's a member on this forum) and cough up another $200 for the OBDII.b to OBDI ecu converter harness.

You get more power with that setup than with an OEM ITR ecu.