Do I need an additional O2 bung??

[g36 monkey]

As most of you know, my plan is to throw a super charger on the 6. I am trying to figure out if I need an additional bung welded into the header(s) or if I can use the existing bungs with the wide band sensor and eliminate the factory style sensors.

I am planning on pulling the headers very soon, and will be wrapping them. I do not want to have to unwrap and rewrap them because of needing a bung later.

Help me please boost warriors.

 

[mcglsr2]

As most of you know, my plan is to throw a super charger on the 6. I am trying to figure out if I need an additional bung welded into the header(s) or if I can use the existing bungs with the wide band sensor and eliminate the factory style sensors.

I am planning on pulling the headers very soon, and will be wrapping them. I do not want to have to unwrap and rewrap them because of needing a bung later.

Help me please boost warriors.

There's a couple ways you can go with this, I will talk about them, and then tell you what I did/do. The answer can also change depending on the type of forced induction.

In your case, with a supercharger, my recommendation is to remove the stock O2 and stick your wideband in there instead. If you are running an OEM ECU and it wants a narrow band input from the O2, a quality O2 system (I personally prefer Zeitronix) will have something called a "simulated narrow band output" or something to that effect. You would basically wire up the wideband output to your gauge (or aftermarket ECU if applicable) and the simulated narrow band to the OEM ECU. I have done this on my 95 (though it's not FI, I still wanted wideband for future tuning). Both of my O2 sensors are widebands, I no longer have a narrow band O2 on the car. The stock plugs for narrow band O2 are disconnected, and I tapped a wire into each of the O2 inputs to the ECU which is fed from the simulated narrow band output on my Zeitronix's. I think I have a wiring diagram, I'll see if I can dig it up.

This same concept can apply to a turbo charged car, however there could be some debate. The potential issue is that some OEM's put the narrow band pretty close to the exhaust turbine of the turbo. This is theoretically bad for a wideband O2, as that would be too much heat for it. The wideband will still function properly, though supposedly it will have a shorter life due to the heat. Most wideband manufactures will say something like "install 1 foot downstream of a turbo" or something like that. Depending on where your OEM bung location is, you can either risk it (which I have done on the 87 CSX to no ill effects) or what a lot of people seem to do, install a new bung further down. Though, personally, I feel like a lot of people do that because they don't realize that their wideband can also take the place of a narrow band via the simulated output, thus they think they need to keep the OEM narrow band to make the ECU happy.

 

[mcglsr2]

Okay, this is how I wired up mine. I will explain the image:

The Zeitronix's are in the middle of the diagram. One for each bank, Left and Right. On the Zeitronix, the simulated narrow band output is the purple wire. To the right of the Zeitronix's in the diagram, is how I wired it into the ECU (you can ignore the connectors, they go into a common 'dash harness' I created - just look at the color of the wires). On one Zeitronix, I changed the purple wire to dark green so I didn't have two purple wires going into the ECU. I found the O2 sensor input using a wiring diagram, and tapped the appropriate purple/dark green wire into the specific input wire. Thus, the Left Zeitronix is feeding the ECU a simulated narrow band on it's Left O2 input, which is what the ECU expects. Same goes for the Right side.

I then disconnected the OEM O2 sensor harnesses under the car, wrapped them to help keep water out, and just left them there. I could have theoretically cut them off, but that would make it really hard to put a stock narrow band back in one day if I wanted to.

Edit: Oh, and I should mention, the car runs fine. The ECU is getting a narrow band signal just like it expects. Also, a pretty cool feature of the Zeitronix, you can fiddle with the simulated narrow band a little. It defaults to 14.7 as the switching point, but if you wanted to "trick" the ECU and have it switch at a higher or lower ratio, you can tell the Zeitronix to switch at a different ratio. The computer will still think it's switching at 14.7, but instead it will be switching at the higher or lower ratio based on what you set in Zeitronix. An easy way to get your car to run richer or leaner without changing anything. Personally, I've never done this as I would rather end up tuning the car based on the wideband. But a cool feature none-the-less. I'm sure other quality brands would have a similar feature.

 

[g36 monkey]

Scott uses very many words. But I called and talked to him on the phone so now I understand. Then I called my tuner and talked to him.

For cars tuning with SCT an on OBD2 setup, the long and the short of it:

You can use your Stock O2 sensors in place, and (in my case with longtubes) add an additional bung in the midpipe provided you are religious about not having exhaust leaks here. This is sufficient for Wideband data.

So, I went ahead and wrapped the headers as is, and when the times comes I will have a bung added to the mid-pipe.

 

[mcglsr2]

Scott uses very many words. But I called and talked to him on the phone so now I understand. Then I called my tuner and talked to him.

For cars tuning with SCT an on OBD2 setup, the long and the short of it:

You can use your Stock O2 sensors in place, and (in my case with longtubes) add an additional bung in the midpipe provided you are religious about not having exhaust leaks here. This is sufficient for Wideband data.

So, I went ahead and wrapped the headers as is, and when the times comes I will have a bung added to the mid-pipe.

Word word word, wordy word word. Words word word word. Word. Word word. More words. Words upon words. With more words. And words. Word.


Having said that: wow, I'm surprised it's okay to have it so far back. Though, I guess if you stick them towards the front of the mid pipes, it's not *that* bad. But still, that's quite a ways away. I guess the only issue with that would be a slight delay in wideband reading vs. actual engine environment, but in the grand scheme of things the delay is probably negligible. Good deal And yes, exhaust leaks before the mid pipe would be Terribleâ„¢