Pre-Turbo Dual Widebands
#1
Pre-Turbo Dual Widebands
Im running a single turbo, but want to run dual widebands for closed loop WOT. Any issues with sensors just downstream of exhaust manifolds before the collector? If there is, then I will be forced to run a single wideband in the downpipe
#3
9 Second Club
Generally the sensors do not like heat or pressure, it can affect lifespan and skew readings. How much I'm not sure.
I think I seen somewhere that the 14.7 units can take account of pressure though, and you can get spacers to lift the sensor out of the airstream a bit which will help the sensor run a bit cooler.
I think I seen somewhere that the 14.7 units can take account of pressure though, and you can get spacers to lift the sensor out of the airstream a bit which will help the sensor run a bit cooler.
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#8
9 Second Club
Nonsense.
They will be fine pre-turbo, just be aware they will be less reliable. But unless they are actually fucked, they will never read as bad as what is wrongly suggested above.
They will be fine pre-turbo, just be aware they will be less reliable. But unless they are actually fucked, they will never read as bad as what is wrongly suggested above.
#10
9 Second Club
Though I make it a habit to not listen to anything from the above poster, they will not "be fine" pre-turbo. The typical bosch LSU sensors aren't rated for the temps and are pressure sensitive. They won't report accurately mounted there and will have a very short life.
I've already explained how to deal with temperature, and if you believe pressure affects them to make them unusable, ( which it doesnt but yes it can affect readings ), it's very easy to build a sampling chamber arrangement which covers any temperature or pressure concerns.
But try them first, pull them out of the manifold a little to keep them cooler and see how they go. Unless you've a terribly inefficient system with horrendous back pressure in there, they will be fine, but yes lifespan can be reduced.
But I'd sooner monitor both banks independently than an average of all 8 where possible.
#11
I just got done reading your guys (Stevie and ForceFed) MS3 vs. Holley battle over on the Bullet, lol.
Either of you guys have some test data using cal/span gases with the sensors exposed to different temperatures and pressures to see how far the calibration can be affected? Would be nice if someone tested a few blends of known O2% and an inert gas mixtures, changed pressure and temperature in a small manifold with the O2 sensor in it, and recorded how the calibration was affected.
Have either of you guys ran pre-turbo widebands and had any negative results?
Thanks for the discussion fellas.
Either of you guys have some test data using cal/span gases with the sensors exposed to different temperatures and pressures to see how far the calibration can be affected? Would be nice if someone tested a few blends of known O2% and an inert gas mixtures, changed pressure and temperature in a small manifold with the O2 sensor in it, and recorded how the calibration was affected.
Have either of you guys ran pre-turbo widebands and had any negative results?
Thanks for the discussion fellas.
#12
9 Second Club
I use them pre-turbo quite often when tuning ( simply because the port is handy on some of the cars ), but have never run them long term.
Never had any problems there, but as said, it can vary and sensor life will be reduced long term.
Doing simple pulls has never posed an issue with sensor heat, but if you were doing longer duration work, racing etc then yes you will need to pull the sensor out of the exhaust flow as I already said.
If you want to run them long term, for closed loop corrections on each bank and ensure a long life, just remote mount the sensor in a small sampling chamber.
Never had any problems there, but as said, it can vary and sensor life will be reduced long term.
Doing simple pulls has never posed an issue with sensor heat, but if you were doing longer duration work, racing etc then yes you will need to pull the sensor out of the exhaust flow as I already said.
If you want to run them long term, for closed loop corrections on each bank and ensure a long life, just remote mount the sensor in a small sampling chamber.
#14
Yes I will have individual cylinder trims and do know how to read plugs....just dont like to because its a pain in the ***.
I want to do CL WOT fuel control. If I get the cylinder trims figured out, then I should be able to do this with a single wideband.
Thanks, looks like I will go this route....but this is just another 800whp street car, not a dedicated race car.
I want to do CL WOT fuel control. If I get the cylinder trims figured out, then I should be able to do this with a single wideband.
Thanks, looks like I will go this route....but this is just another 800whp street car, not a dedicated race car.
#15
8 Second Club
iTrader: (4)
And how many cars have you used pre-turbo widebands on ?
I've already explained how to deal with temperature, and if you believe pressure affects them to make them unusable, ( which it doesnt but yes it can affect readings ), it's very easy to build a sampling chamber arrangement which covers any temperature or pressure concerns.
But try them first, pull them out of the manifold a little to keep them cooler and see how they go. Unless you've a terribly inefficient system with horrendous back pressure in there, they will be fine, but yes lifespan can be reduced.
But I'd sooner monitor both banks independently than an average of all 8 where possible.
I've already explained how to deal with temperature, and if you believe pressure affects them to make them unusable, ( which it doesnt but yes it can affect readings ), it's very easy to build a sampling chamber arrangement which covers any temperature or pressure concerns.
But try them first, pull them out of the manifold a little to keep them cooler and see how they go. Unless you've a terribly inefficient system with horrendous back pressure in there, they will be fine, but yes lifespan can be reduced.
But I'd sooner monitor both banks independently than an average of all 8 where possible.
#16
9 Second Club
Contact any of the WB02 suppliers that use a Bosch LSUXX sensor and they will tell you the sensors are not accurate in a pressurized environment pre-turbo. I know because I called Innovate and asked after seeing a few of the engine master videos with the MS running a WB02 on each cylinder. They said the sensor life will be VERY short and the readings would be inaccurate.
And I know they can be used...because I've done so. And already explained very clearly how they can be used long term if you so desire too.
#17
I find this thread helpful to me as I was planning to run 02s on each bank with my huron t4 hit. I have a friend who is not a member on this site but he runs them on each bank with his kit and had had no problems with it so far. stevie you said they can be ran in a small sampling chamber. can you shed any ideas on how I could accomplish this? it seems doable to me and having a wide band on each bank would have its benefits no doubt..I was wanting to run a wideband post turbo to tune with, then use regular 02s on each bank pre turbo. my be someone can tell me if this might be a bad idea.. if I could get the 02s to live it seems to me like this would be the way to go
#18
8 Second Club
iTrader: (4)
Innovate arent reliable no matter where they're installed ! Best WB of all if you want faulty sensors all the time. FFS sensor life with them is short even nowhere near pressure or a turbo.
And I know they can be used...because I've done so. And already explained very clearly how they can be used long term if you so desire too.
And I know they can be used...because I've done so. And already explained very clearly how they can be used long term if you so desire too.
Innovate uses the same BOSCH LSU sensor most other manufacturers use. We are talking about the nature of a WB02 sensor and how they work. They all work the same for the most part, and will report inaccurately pre-turbo, or even on an NA engine with high exhaust back pressure.
Straight from BOSCH... PG.23
A pressure change of the measured gas gives a deviation of the sensor
output signal
output signal
http://www.daytona-sensors.com/download/Bosch_LSU4.pdf
#19
9 Second Club
Huh?
Innovate uses the same BOSCH LSU sensor most other manufacturers use. We are talking about the nature of a WB02 sensor and how they work. They all work the same for the most part, and will report inaccurately pre-turbo, or even on an NA engine with high exhaust back pressure.
Straight from BOSCH... PG.23
http://www.daytona-sensors.com/download/Bosch_LSU4.pdf
Innovate uses the same BOSCH LSU sensor most other manufacturers use. We are talking about the nature of a WB02 sensor and how they work. They all work the same for the most part, and will report inaccurately pre-turbo, or even on an NA engine with high exhaust back pressure.
Straight from BOSCH... PG.23
http://www.daytona-sensors.com/download/Bosch_LSU4.pdf
The issue there isnt the sensor, it's Innovate and a separate thing from the heat/pressure aspect which I have already covered and agreed it can skew readings, but by no means makes them unusable.
@boosted.
The easiest way to describe it is install the sensor a little like a w/g. ie small tube to a small chamber where you install the sensor, and then route the discharge back into the downpipe ( or you could vent it to atmos, but I'm sure the sound would be irritating )
If you want to ensure this never sees any significant pressure make the discharge is slightly larger than the supply hole. Either way keep the supply hole small as ultimately this will bypass some exhaust gasses past the turbo although done right it's an insignificant amount.
You dont need a huge volume of gas over the sensor
It's common place on old Mini's where the siamese ports/valve events can badly affect fuel distribution into each cylinder when trying to use fuel injection, hence they need to closely monitor AFR's for the relevant cylinders.
#20
8 Second Club
iTrader: (4)
We arent' discussing controller brands. We are talking about the nature of the sensor itself when exposed to pressure. That's a link from the sensor manufacturer, not the controller or innovate. If a sensor sees elevated pressure ratios mounted pre-turbo it will skew the readings, regardless of the controller used. It's a sealed pressure system behind the turbo. Make all the chambers you want, it's still going to see 2-3:1 pressure ratios on most turbo kits and the readings will be wrong.
I understand what your talking about with heat, I run one of these on my setup because it's so close to the turbine and my DP is short. Running a WB02 sensor pre turbo is plain wrong, no matter how you do it.
I understand what your talking about with heat, I run one of these on my setup because it's so close to the turbine and my DP is short. Running a WB02 sensor pre turbo is plain wrong, no matter how you do it.