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On longtubes, if you have 2 bungs next to eachother, one in front of the other, does it matter which bung is used for the front o2 and which is used for the wideband? The bungs are literally 2" away from each other. Didn't want one to somehow block the other and give a different reading (even though I don't think that's possible). Thanks!
Should not matter as long as they are in front of the cats.
No that is not correct. Yes it matters. If you are using your WB for anytype of calibration then it needs to be the front or first sensor. A sensor has a trailing contamination tail and your normal sensor can pollute the WB sensor and make the readings not as accurate. If you are just mounting a gauge for looks then it will not matter.
Well in this case, it would be used for tuning. I figured the front o2 is still the one sending the main readings so that one should be in front. I'm not doing wideband simulation or anything. So stock o2 in front of wideband in this case, sound correct?
Originally Posted by J.Abbott
No that is not correct. Yes it matters. If you are using your WB for anytype of calibration then it needs to be the front or first sensor. A sensor has a trailing contamination tail and your normal sensor can pollute the WB sensor and make the readings not as accurate. If you are just mounting a gauge for looks then it will not matter.
if you are mounting it permanently for observation purposes, it's not a huge deal but if you are only installing to tune then removing, just pull the driver side narrowband and use that bung for the wideband, put the car in open loop and tune it, then put it back in closed loop with the narrowband for regular use.
Mine will be up permanently for this install. Thanks for that advice!
Originally Posted by Higgs Boson
if you are mounting it permanently for observation purposes, it's not a huge deal but if you are only installing to tune then removing, just pull the driver side narrowband and use that bung for the wideband, put the car in open loop and tune it, then put it back in closed loop with the narrowband for regular use.
Well in this case, it would be used for tuning. I figured the front o2 is still the one sending the main readings so that one should be in front. I'm not doing wideband simulation or anything. So stock o2 in front of wideband in this case, sound correct?
No, while you are performing any tuning the WB needs to be in front. You are corrupting the data in the WB if it is behind the regular 02 sensor. The WB is always in front. The reason I asked if you were just using is as a gauge in the dash to monitor is because in the case the accuracy of the WB is not really important. For tuning though it is important.
if you are mounting it permanently for observation purposes, it's not a huge deal but if you are only installing to tune then removing, just pull the driver side narrowband and use that bung for the wideband, put the car in open loop and tune it, then put it back in closed loop with the narrowband for regular use.
So just to reiterate: during tuning, WB is in the front slot (or remove the NB and place a plug in its spot, I'm assuming would work as well). After tuning, the NB should go back in the front slot, and the WB is just monitoring while the NB does corrections?
I think I'm only confused because in previous applications (usually 4 cyl) I would only have a wideband and would simulate the NB through the WB via tuning software. I'm not familiar with how these cars are tuned so I'm not sure how everything needs to be setup.
Originally Posted by J.Abbott
No, while you are performing any tuning the WB needs to be in front. You are corrupting the data in the WB if it is behind the regular 02 sensor. The WB is always in front. The reason I asked if you were just using is as a gauge in the dash to monitor is because in the case the accuracy of the WB is not really important. For tuning though it is important.
So just to reiterate: during tuning, WB is in the front slot (or remove the NB and place a plug in its spot, I'm assuming would work as well). After tuning, the NB should go back in the front slot, and the WB is just monitoring while the NB does corrections?
I think I'm only confused because in previous applications (usually 4 cyl) I would only have a wideband and would simulate the NB through the WB via tuning software. I'm not familiar with how these cars are tuned so I'm not sure how everything needs to be setup.
If you are tuning it, you can leave the wideband in, just put it in front and the NB in back (if they are that close). That way you don't have to unhook the NB at all or leave it dangling.
Basically, put whichever one is critical for adjustments in front.
After tuning is done, all adjustments are made through the NB sensor though, correct? So the NB would have to go back upfront and WB behind it? Or does the WB stay up front forever? That's the part I'm confused about. I'm not sure if the WB is used for corrections like my previous builds or if it's just there to set a more accurate base tune, then just monitoring.
Originally Posted by Higgs Boson
If you are tuning it, you can leave the wideband in, just put it in front and the NB in back (if they are that close). That way you don't have to unhook the NB at all or leave it dangling.
Basically, put whichever one is critical for adjustments in front.
After tuning is done, all adjustments are made through the NB sensor though, correct? So the NB would have to go back upfront and WB behind it? Or does the WB stay up front forever? That's the part I'm confused about. I'm not sure if the WB is used for corrections like my previous builds or if it's just there to set a more accurate base tune, then just monitoring.
Tune the car in open loop (disabled narrowbands) with the wideband in front.
When you are done, put the car back in closed loop so the narrowbands can assist with fuel trims keeping fuel in line for minor changes in temp, altitude, etc. with the narrowbands in front.
The wideband is not used for corrections unless you are actively tuning the car and making changes to the airflow tables. Base tune then monitoring.
Fords (like the Mustang) use widebands full time in place of the narrowbands and even correct real time at full throttle. GM is way behind in this sense.
I was unaware of that. Thanks for enlightening me. What causes the first sensor to have a trailing contamination tail? If there, say 10 inches, between the first bung and the second bung does that eliminate the contamination issue?
Originally Posted by J.Abbott
No that is not correct. Yes it matters. If you are using your WB for anytype of calibration then it needs to be the front or first sensor. A sensor has a trailing contamination tail and your normal sensor can pollute the WB sensor and make the readings not as accurate. If you are just mounting a gauge for looks then it will not matter.
Just out of curiosity, how do shops tune cars that DON'T have a wideband in them? Do they install their own for tuning purposes then put back in the narrowband?