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Install WB/O2 in middle of exhaust to tune...

2K views 42 replies 15 participants last post by  Lagtime 
#1 ·
I was told by Innovate Motorsports that I should be ok mounting the sensor about halfway in the exhaust...actually they said it really didn't matter where as long as the sensor doesn't get too hot. If it does it will show an "error" message and he suggested to just mount it in the middel of the whole exhaust.

I myself really don't see any problems with that considering that when I dyno the "sniffer" is all the way at the back of the exhaust and it seems to work ok, but I guess I really don't have anything to compare it to either.

Just getting some ideas from you guys. The Wideband comes in Thursday...so I should be tuned by Sunday so I can run it at the track a full 1/4 pass and see what it will do.:) Hmmm...any guesses as far as what it will do?

Thanks for reading.

Later
 
#2 ·
I've had FJO on two supras...both sensors were mounted at the top of the DP. Farther back it's mounted the slower it is to respond...meaning it may be a few RPM behind reality.



It's the empty bung...
 
#3 ·
Philly Single said:
I've had FJO on two supras...both sensors were mounted at the top of the DP. Farther back it's mounted the slower it is to respond...meaning it may be a few RPM behind reality.



It's the empty bung...
The NTK sensor is pressure sensitive and the Bosch sensor is temperature sensitive. I have heard of Supra owners getting away with putting the Bosch sensor in the DP, but I am told by Innovate Motorsports that just MAY be too hot. They are used to getting feedback from the RX-7 guys and I guess they have hotter temps that Supras from what I understand because when I told him the max temp EVER coming out of the header would be around 1550 degrees F he said that temp is low enough to not really worry about too much...he just gave me a VERY SAFE placement of the O2 sensor...not so much a HAVE TOO placement. If you know what I mean by all that.

So, I guess my main question would be will the Bosch sensor work OK that close to the turbo outlet without getting an error? I think that I have heard on here of people doing it, but I guess I need a confirmation on it.

Thanks Philly

Later
 
#6 ·
DaveH said:
Innovate told me the same thing, but I put my sensor in a spot similar to Philly's, just because I already had the bung there. The Bosch sensor has worked fine there.
Not one single error yet then?:cool: How long have you had it installed on the car now? What do you run your a/f ratio at and what do you think about the functionality of the system itself?

Thanks Dave

Later
 
#7 ·
Olivier Caza said:
Around 620-640 rwhp at about 26-27 psi. 10.45 at 133-134.














Just guessing...out of the blue!! Good luck!! :D

-Olivier
I might go ahead and go for the full 28.:D We'll see what happens. Thanks for the guesstimate and I will keep everyone posted.

Later
 
#8 ·
Dave,

How many inches or feet would you say your bung is mounted from the outlet of the turbo? Just trying to get this thing right the first time.;)

Thanks again

Later
 
#9 ·
Not a single error yet, I've only ran the sensor maybe 5 or 6 hours total so far. I have the sensor 6-7" behind the V-band.

I have normal driving a/f's in the 13:1 range, and wot is in the 11.8:1 range on the street. I haven't used the internal logging with the unit yet, I need to get the output fed into the aem so I can log a/f against rpm. Is the Innovate rpm adapter out yet?
 
#10 ·
DaveH said:
Not a single error yet, I've only ran the sensor maybe 5 or 6 hours total so far. I have the sensor 6-7" behind the V-band.

I have normal driving a/f's in the 13:1 range, and wot is in the 11.8:1 range on the street. I haven't used the internal logging with the unit yet, I need to get the output fed into the aem so I can log a/f against rpm. Is the Innovate rpm adapter out yet?
Thanks for the info Dave.

They said that they would more than likely be shipping them out Friday. I told them to give me a call and let me know they have it ready for shipment.:D I just talked to them today.

Later
 
#11 ·
TT_6SPD_95 said:
The NTK sensor is pressure sensitive and the Bosch sensor is temperature sensitive. I have heard of Supra owners getting away with putting the Bosch sensor in the DP, but I am told by Innovate Motorsports that just MAY be too hot. They are used to getting feedback from the RX-7 guys and I guess they have hotter temps that Supras from what I understand because when I told him the max temp EVER coming out of the header would be around 1550 degrees F he said that temp is low enough to not really worry about too much...he just gave me a VERY SAFE placement of the O2 sensor...not so much a HAVE TOO placement. If you know what I mean by all that.

So, I guess my main question would be will the Bosch sensor work OK that close to the turbo outlet without getting an error? I think that I have heard on here of people doing it, but I guess I need a confirmation on it.

Thanks Philly

Later
Tony,

There is no such thing as a PRESSURE SENSITIVE o2 sensor. Imagine what a person who has a straight pipe exiting the side of the car. There back pressure would be pretty much non-existing. o2 sensors have ceramic heating elements in them that are designed to operate at a certian temperature. The same reason why you cannot just leave an o2 sensor in the exhaust path unpowered because be the heating element does not get a chance to warm the o2 sensor enough to protect it from exhaust gas flow. Most o2 manufacturers will tell u 18 inches from the head is the ideal position to place the primary o2 sensor. I've spoken with NGK and that is what the recommend. If u measure the header length, 18 inches is where most people have theirs.

FYI- the ntk (daughter company of ngk) sensor that fjo uses comes in a bosch box.

Good luck,
Sid
 
#12 ·
sidwin said:
Tony,

There is no such thing as a PRESSURE SENSITIVE o2 sensor. Imagine what a person who has a straight pipe exiting the side of the car. There back pressure would be pretty much non-existing. o2 sensors have ceramic heating elements in them that are designed to operate at a certian temperature. The same reason why you cannot just leave an o2 sensor in the exhaust path unpowered because be the heating element does not get a chance to warm the o2 sensor enough to protect it from exhaust gas flow. Most o2 manufacturers will tell u 18 inches from the head is the ideal position to place the primary o2 sensor. I've spoken with NGK and that is what the recommend. If u measure the header length, 18 inches is where most people have theirs.

FYI- the ntk (daughter company of ngk) sensor that fjo uses comes in a bosch box.

Good luck,
Sid
So, by theory should the Bosch sensor that I am talking about be ok mounted 18 inches from the outlet of the turbo? I guess the only reason the question has came up is because when I was talking to them they have had some problems with the sensor getting too hot, but all the cars that have had those problems have been RX7's, but that doesn't tell me that the same thing won't happen to a Supra.

As far as "pressure sensitive" goes...that is what they told me the different between the ntk and the bosh sensor was for some reason. Maybe they were talking about something different at the time. Not sure.

Thanks for the reply. Appreciated.

Later
 
#14 ·
I really disagree, as do the folks that build the Tech edge WBO2, both the Bosch, and the NTK ARE pressure sensitive due to the fact that the sensors use diffusion(which is passive) in their operation. Forced induction can create a situation where expected diffusion is influenced by pressure waves from the turbo. In addition Bosch specifies a max temp of 1560 degrees for the L1H1. Even if you do not vbelieve this, why not simply utilise a bung 18" or so rear of the turbo just in case the manufacturer of the component is right ;). In the RX7 community I have been told that when two sensors are placed one right behind the turbo, and one 18" downstream, that the difference can be as much as a full point. Further there has been discussion on this forum RE heat, and its ability to cause readings up to a point richer than actual. Here is an exerpt from the TE site;

"Wideband Sensor Positioning
The wideband sensor must be carefully placed in order to prevent damage to the sensor itself and to maximise accuracy. Also, if you use the sensor's output directly (via the simulated narrowband output) to drive your ECU then you should be doubly careful. Please follow all of these "rules" :

The sensor should always be placed on the engine side of a catalytic converter, unless you are testing the effectiveness of the convertor itself.
The gas temperature to the sensor should never exceed 850 degrees C (about 1560 degrees Fahrenheit).
The sensor should never be run without power to the WB unit (a hot sensor burns off carbon residues)
Always have the long axis of the sensor perpendicular to the gas flow (stops sensor clogging)
Position the sensor vertically or at most between 10 o'clock to the 2 o'clock position (this avoids cracking the internal ceramic structure should moisture condense internally)
We don't recommend using a short sections of exhaust pipe shoved up your tailpipe. A specially welded additional bung is the best mounting strategy.
The sensor reads the partial pressure of gases in the exhaust and infers the AFR, rather than by measuring some magical AFR directly. This may be an issue on forced induction, and in particular, on turbo-charged engines.

AFRs will indicate richer than they are, causing you to run leaner than you think.
Lean AFR's will be richer (or less lean) than indicted.
A solution is to ensure you locate your sensor away from the turbo, and certainly on the exhaust (low pressure) side of the turbo rather than the engine side. "
So, do what works for you, but for anyone asking the question, here are the facts as stated by folks whom most would consider experts. Regards, Carl Byck
 
#15 ·
Here is a link to a picture of why SIDWIN is not right
http://techedge.com.au/vehicle/wbo2/wbntk.htm
DaveH, how do you know you readings are correct if you do not have a bung in the recomended location? Carl
97T66 RSP
88 RX7 widebody road race car (sorry, that's the best I can do for credentials ;))
 
#23 ·
im glad these innovative motorposrts WB/02's are working well, anyone have pics of where they put their unit in the car?

Brett
 
#24 · (Edited)
in2twins said:
Here is a link to a picture of why SIDWIN is not right
http://techedge.com.au/vehicle/wbo2/wbntk.htm
DaveH, how do you know you readings are correct if you do not have a bung in the recomended location? Carl
97T66 RSP
88 RX7 widebody road race car (sorry, that's the best I can do for credentials ;))
How am i not right in the that pic? I've ran almost every wbo2 known to man :) I had the first Techedge from Peter almost 3 yrs ago and motec tested on my car. There is a reason why i have the FJO now ;) i said that my NTK (NGK) sensor came in a bosch box. I've bought 5 NTK sensors from 3 different sources and they all come in bosch boxes. I've spoken directly with FJO and NGK about where to position my sensor(s). I've never used the WB that tony is using and i stated that.

So u mean to tell me u put the o2 sensor 18 inches closer and saw 1 a/f difference? LOL. dude u must have a serious exhaust leak... The reason why up probably saw 1 af difference is you put the sensor in a heat range that is beyond the sensor's tolerances.

Imagine my car where the o2 right now roughly midway down the midpipe. The car constantly reads 14.7:1 at idle and 12:1 at wot. The car read the same on the dyno. If you are right then i should be running 13:1 with 30 psi boost and my egt were 700 C right behind the turbo. If my a/f was 13:1 don't u think my egt would indicate that? Why would my fjo and the motec wbo2 on the dyno read the same a/f? The motec is in my tailpipe roughly 40 inches away. Imagine tuning the car for what u think 12:1 on a dynojet then seeing 12.5:1 on the street but actually with your theory then I would be running 13.5:1 @ 28 psi.... Imagine the metal shooting out of the exhaust j/k

Most of our headers have runners near 18 inches long. That is probably why every single turbo kit has the stock primary o2 sensor right near the top of the pipe.

Even when I spoke with Jet-Hot, which is 1 hr away from me, the first thing they told me was make sure i take into consideration that a turbo charged vehicle will run considerably hotter than a NA car. Why would NGK said becareful of putting it too close to the head? I guess they must be wrong too.

Fred at FJO said that the distance is as important as the angle the sensor is pointing. You definitely don't want it at the 6 o'clock position because it will collect moisture. Dynojet guarentees their WB which is shoved in the tailpipe to be exact within +-1 of .1 a/f. Same thing with FJO.

Good luck,
Sid
 
#25 ·
in2twins said:
Here is a link to a picture of why SIDWIN is not right
http://techedge.com.au/vehicle/wbo2/wbntk.htm
DaveH, how do you know you readings are correct if you do not have a bung in the recomended location? Carl
I had ~11.6:1 a/f on the Dynojet dyno using their sensor, and ~11.9:1 on the street so I guess it's pretty close. I just said that I didn't get a error from the LM1, not that I know for a fact that it's reading perfect a/f.
 
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