I have a stock ITR motor & ECU. When installing the AEM wideband gauge & sensor, does the wideband sensor replace the stock narrowband or do I need to have the included bung welded to manifold and use both stock narrowband and AEM wideband?

 

the AEM wideband replaces the stock narrowband O2 sensor. since your using a stock ecu just remember to run the narrowband output from the wideband to the ECU.