When getting a wideband o2 sensor, is it installed in addition to the stock one or in place of?

 

use as a addition..unless of course your using standalone management, like haltech or such, which i know nothing about...but for using on a air fuel guage...add the wideband into your exhaust, the stock will still work with the ecu, and the wideband will report to the air fuel guage more accurate than a stock o2 sensor...might want to check the drag racing forum..or forced induction

 

Either weld in another bung or use it in place of, since some WB systems have a narrowband output feature.