can narrow bands be used for to tune to 13.2 @ WOT

[FLTRI]

Can a narrow band O2 sensor be used to tune to a specific AFR richer than 14.4:1?
In other words, can a narrow band O2 sensor be effectively used to tune to a target AFR of say 13.2:1?
Bob

[rbabos]

Can a narrow band O2 sensor be used to tune to a specific AFR richer than 14.4:1?
In other words, can a narrow band O2 sensor be effectively used to tune to a target AFR of say 13.2:1?
Bob

Yes, assuming the location is good to get decent sampling. Won't last long though.
Ron

[FLTRI]

Can a narrow band O2 sensor be used to tune to a specific AFR richer than 14.4:1?
In other words, can a narrow band O2 sensor be effectively used to tune to a target AFR of say 13.2:1?
Bob

Yes, assuming the location is good to get decent sampling. Won't last long though.
Ron

How would you get 13.2 from a narrow band and why would it not last?
Bob

[ultraswede]

The NB cant read anything near that rich AFR, it will bottom out at 1v much earlier.

Having said that, with a correctly populated VE table, by using the NB, then setting the AFR table to 13,2 should get you pretty close.

But you allready knew all this, right?


http://www.ztechz.net/id12.html

[rbabos]

Can a narrow band O2 sensor be used to tune to a specific AFR richer than 14.4:1?
In other words, can a narrow band O2 sensor be effectively used to tune to a target AFR of say 13.2:1?
Bob

Yes, assuming the location is good to get decent sampling. Won't last long though.
Ron

How would you get 13.2 from a narrow band and why would it not last?
Bob

Well actually 13.65 seems to be the clb limit of 836. Lamda shows .871 at 13.2 afr
As far as I know the sensor will read this . It's at the upper limit of operation and since rich degrades sensors fast, in short order it will no longer be able to hit that voltage.
Other than causual conversation, why did you bring this up since no normal person would do this other than experimenting?
Ron

[TXP]

Interesting twist. Of course you can. Once your VE's are correctly calibrated and synchronized, the AFR Command is changed to desired. Nothing really different than using the Widebands and setting all points to 13.2 and then changing them back to whatever commanded afr you desire and verifying.

[ultraswede]

As can be seen in the graph I posted;
The sensor output is the same from 14,2 AFR and richer.
i.e. There is no way to tell if the engine is running 14,1 or 13,2, just reading the NBs.

[Coyote]

Interesting twist. Of course you can. Once your VE's are correctly calibrated and synchronized, the AFR Command is changed to desired. Nothing really different than using the Widebands and setting all points to 13.2 and then changing them back to whatever commanded afr you desire and verifying.

From what little I know I agree. You should be able to calculate it based on VE's populated from a leaner value. My understanding is that getting those values within the range of the sensor is the problem at high MAP values as it runs the engine much hotter.

[FLTRI]

Take a peek at this:
http://tuneyourharley.com/biketech/content/narrow-band-o2-sensor
Read about narrow band sensor output and I believe this will open some eyes.
Bob
Note: Notice the difference between TYH narrow band voltage output compared to the one ultraswede posted.

[Coyote]

I don't think you can read, accurately, 13.2. You can however calculate it based on readings within the sensors range. 

It would seem to me that reading a value vs tuning to a value are two different things so I'm not sure what your point is.

[FLTRI]

Keith,
Did you look at the NBO2 table showing voltage to AFR to lambda?
Looks like 13.2 = 800-900mv.
Based on this test (and my personal racing experiences) the sensor is reliable to use for tuning richer than Stoich, right?
There is a lot of misinformation concerning the NBO2 sensor and how it works.
Thought maybe posting actual testing results would help this discussion.
Bob

[Coyote]

Bob, it looks to me as if the sensor is useless in that range as it varies wildly over temperature.  In the sensors active range, it is very stable over temperature. This is where all the lines converge together.

At least that would be my take on it

[FLTRI]

Using the graph and the associated EGT what AFR range would 900mv relate to?
Bob
Note: A properly tuned engine should produce ~1200 degs @ WOT...which is the condition we need say 13.2.

[TXP]

[quote
It would seem to me that reading a value vs tuning to a value are two different things so I'm not sure what your point is.
][/quote]

If your going to rely on the NBO2 for feedback while riding, does it not follow that using it during the tuning process would yield a closer percentage of VE to be corrected to? Apparently, the OEM beleives it works well enough. This debate will never end because no matter who shows what spec some will simply never accept NBO2 as part of the tuning process or part of the tuners arsenal. Quite frankly, some just want to bash anything SC has said as evidenced in so many threads. I know of no one who understands the Delphi Systems any better than Steve. But hey, what do I know?

[Coyote]

If your going to rely on the NBO2 for feedback while riding, does it not follow that using it during the tuning process would yield a closer percentage of VE to be corrected to?

I agree, that's what I said.

SC has nothing at all to do with this discussion. It's generic in nature and not tuner specific.

The question is what are the ways to use the sensor.

[FLTRI]

SC has nothing at all to do with this discussion.

Yes that is true...only because he got ousted. He is THE go to guy for flash tuning and especially O2 sensor utilization IMO.

FWIW, as I mentioned a while ago, we utilized NBO2 sensors (spec class) to monitor 12.8 AFR.
The engine builder tuned the engine for best power (12.8 in this example) read the O2 sensor output, ~.89v IIRC. We then used the on board d/a system to monitor and keep tuned to that specific voltage to hold to 12.8 AFR.

Can the sensor be used for tuning to other AFR without voltage verification? Hell no.
But it can be used to target a specific voltage/AFR. ie: 900mv = 13.2 @ 1200deg (WOT)

Bob

[rbabos]

Interesting stuff. I did know new NB sensors had about 1.2mv from my torch and multimeter testing. Old ones I had only went to .850 and could never hit the richer afrs in that case.
Ron

[Hilly13]

Interesting stuff. I did know new NB sensors had about 1.2mv from my torch and multimeter testing. Old ones I had only went to .850 and could never hit the richer afrs in that case.
Ron

By new Ron do you mean the self heated type verses the 18mm ones or is there a newer vesion of both?

[wurk_truk]

IIFRC, Ron means new out of the box as compared to used ones at the end of their life span.

I find this interesting.  I can understand how it worked in the past for Bob, too.  I know that by myself, I would be lost.  But if others work on this...  it could be a very nice tool for tuning.  From my own understanding... a WB operates at like 20hz.  AT 5k rpms, the firing cycles are around 50hz, so there will be a bit of lost data.  The NBs are more robust, no pumping circuit, and CAN operate at that level, I just wish for someone to show it is accurate as the WBs or moreso.  For the present, I am a fan of WBs in the upper map and rpm ranges.  But...  I, myself, am NOT wedded to ANY orthodoxy.

[rbabos]

Interesting stuff. I did know new NB sensors had about 1.2mv from my torch and multimeter testing. Old ones I had only went to .850 and could never hit the richer afrs in that case.
Ron

By new Ron do you mean the self heated type verses the 18mm ones or is there a newer vesion of both?

I tested the none heated ones just for chits and giggles. Other reason was to determine +/- to splice a different model to the harley plug. I was also amazed at once hot how fast the volts drop and returns with the flame on and off the tip. Like instant.
Ron

[FLTRI]

So the question still remains unanswered.
I was hoping to get some of the knowledgable tuners and O2 experts engaged in this thread.
Bob

[mayor]

Based on the posted info, as long as the software is there to collect the data...looks like it's a non issue to use NB for richer settings. 

I also have a hunch that this question was a set up to a soon to be or already released new feature of a tuning system.   

[Hilly13]

If so Mayor I look foward to reading about it 

[Jeffd]

Based on the posted info, as long as the software is there to collect the data...looks like it's a non issue to use NB for richer settings. 

I also have a hunch that this question was a set up to a soon to be or already released new feature of a tuning system.   

I bet you are right.  is there a way to monitor exhaust temps currently?  seems that is the key factor.

[strokerjlk]

I also have a hunch that this question was a set up to a soon to be or already released new feature of a tuning system.   

Ummm hummmm. 
Old news Bob .