I have a set of shorty headers on my truck. Each header has an O2 bung in the collector. Currently, my stock exhaust system has the O2 sensor mounted in a short balance tube between the 2 bank pipes just before they enter the first catalytic converter. I'm looking to install a new exhaust system. Where to put the O2 sensor?
The header bung(s) are really convenient. Would placing the sensor in one header collector cause any issues for proper metering of oxygen content being that it would only be sensing that one bank? Would the close proximity to the exhaust ports be too hot for the stock sensor?
Or, should I place a sensor in each bank and wire the 2 sensors in parallel? I suspect wiring them in series would cause false readings. But, would 2 sensors create a funky reading? I suppose these sensors register their findings by resistance variations in the 12v power in a similar manner as electric temp and pressure sensors do. I also suppose that both would be read as whichever offers the strongest signal.
Or, should I stick with the "stock" method and install a bung centered in the balance tube?
The new headers you have wih the bung in the collectors are more for the Sequential EFI system which each cylinder get's it's own injector pulse width from the EEC. Since our system of Speed Density for the trucks is batch fired, there is only "1" bung and that is the right @ the "Y". That's the best location for your setup. If you did the Speed Density to MAF setup, then having the O2 bung in the colector is a (+). You will need 1 O2 sensor in each bank so the EEC can monitor if either side is running Rich or Lean.
I have thought about the notion of wiring in "2" HEGO sensors, since all I would need to do is get a driver side exhaust manifold with the O2 sensor bung and use the passenger side one together. For some reason, the passenger side exhaust manifold had an O2 sensor bung. I think someone got it by mistake.
Edit: If I'm wrong, someone correct me. This was my understanding after much research, but I could have been mislead in my reading of the O2 sensor and the placement in the collectors and "Y" pipe.
You only need one oxygen sensor,I put mine in the passenger's side collector,engine has ran fine for 2 years just reading one bank.(well,it was running fine,now needs a timing chain so it will run again,waiting for it to stop raining for more than a day so I can fix it.)