legacycentral bbs

So my wideband sensor is on its way I was wondering if the stock narrowband location is a good spot to put it. The new one comes with a weld in bung if its not, also if I put the bung in someplace else is there any advantages to running a wideband along side of the narrowband? I am using a haltech elite standalone also.

Sent from my XT1650 using Tapatalk

From the haltech website:

Broadly speaking there are two different types of O2 sensor available, wideband and narrowband. Both sensors have their place in tuning an engine, narrowband sensors are designed to be used in conjunction with a catalytic converter.

In brief a catalytic converter works on a saturate/starve principal where the fuel injection system saturates the converter then starves the converter, i.e. it runs rich of 14.7:1 (saturate) then lean of 14.7:1 (starve) and as such a narrowband O2 sensor only reads rich of 14.7:1 or lean of 14.7:1.

Unfortunately a narrowband O2 sensor is unable to determine exactly how rich or exactly how lean the engine is running making it useless for full power engine calibration (as under full power we need to run the engine much richer that 14.7:1 so we don’t melt pistons!).

A wideband O2 sensor on the other hand is designed to read a much broader spectrum of air to fuel ratios (The Haltech CAN wideband reads accurately from 10:1 – 20:1 air fuel ratio) which makes it the ideal tool for engine calibration.

Narrowband or Wideband?
For engine calibration purposes, diagnostic purposes, datalogging and performance work a wideband O2 sensor is the correct tool for the job. For emissions related purposes used in conjunction with catalytic converters a narrowband O2 sensor is essential (normally with a wideband O2 sensor in place as well for the full power engine calibration).

In my personal experience I've opted to use only wideband. I've also had no problems with emissions doing so.

As for placement of the wideband o2 sensor the general rule of thumb is no closer than 5in. From the turbo to maintain longevity of the sensor. I personally place mine at the end of the down pipe, most aftermarket down pipes for Subaru have a bung mounted 24 or more inches at the end of the down pipe. Its also been noted by many wideband o2 sensor manufactures that the bung should be mounted at an angle towards the stream of flow rather than straight up and down..

Yeah I've read to not put it up and down too. I don't have any catalytic converters on my car anymore and no emissions testing where I live. Looks like I have some welding to do when it gets here.

Sent from my XT1650 using Tapatalk

I'll give you my take on things; the issue with putting further away from the engine (end of the DP vs. top) is the delay in readings. Under steady state tuning it wouldn't be an issue, but if you're using the ECU for real time tuning adjustments closer the sensor is to the engine the better.

I have my wideband in the stock O2 sensor location. I have replaced the sensor once over the life/years I've had the wideband installed.