I'm getting ready to install my headers, which are ceramic coated and have the stock O2 bung already welded on. My question is what to do when I want to start tuning with a wide band? I don't want to screw up the coating on the headers by welding on another bung. I'm assuming the car always needs the stock O2 (switching) sensor to run properly, or can the WB be used for datalogging/tuning and at the same time feed the ECM with an AFR in input?

I'm thinking about welding the WB bung on the inlet side of the cat. This way I'll be upstream of the converter and won't fudge up the coating on my headers. Does anyone know if this will work?

Thanks

 

You can use the LM1 to also run your car (2 analog outputs), some other brands may also claim this, but I know for fact that the LM1 can (been running my car on it).
It's also OK if you want to put in the WB in the Pre-cat location, which will show you both banks of the engine. This may cause you some confusion if for some reason the WB doesn't agree with closed loop, because closed loop only sees one bank, and may be different than the other due to misfires, injector problems, etc. Having the sensor downstream may introduce some lag, but you'll get used to it, and probably won't even notice it. The sensor may even live a longer life farther away from the exhaust ports - just be sure to install it with the tip angled down - there's a bunch of water in exhaust, and when it condenses an pools, it'll soak and rust and damage your sensor.

 

i welded mine in exact same position as 02 sensor just in other exhaust pipe. when duals installed we placed the stock 02 in bung in ext pipe just behind collector. so seemed reasonable to place WB at mirror image same. be aware the header manufacturer offers an adapter to place on end of the collector. bolt on. OBTW. bosch stock 02 reads about 15.2 on WB in CL at idle fully warmed engine ?