Need info on swap consisting of 99Si head ITR BLOCK, using p73 comp. from 97/98 ITR. The computer is OBDII but there is no cat to bolt to my header that would house the second o2. Then theres the issue of a cat back exhaust. Nobody makes exhaust for this set up and a muffler shop cant bend pipe for **** so any suggestions are appreciated.

 

get a test pipe with o2 bung. or get ecu rechipped (you'll need to anyway to raise rev limiter and then remove 2nd o2 programs).

You might be better off with a 94-95 gsr ecu rechipped with the a/f maps you need and higher rev limiter. no 2nd o2 sensor, and retains the factory knock sensors.

As far as exhaust, any good shop can do one up for you with mandrel bends...

What chassis is this going into?

 

96EK chassis .