The OD of the ITR throttle body is slightly larger than the other B-series throttle bodies.

You might need a different intake coupler if you have an aftermarket intake or you can use an original ITR intake pipe.

If you have an OBD-1 Integra, then you should get a JDM ITR throttle body with the EVAP purge port. If you have an OBD-2 Integra, then you should get a USDM ITR throttle body.

Throttle response is slightly better, but I'm not sure about the increases in WOT power.