Thoughts on wideband location (18 Frontier)

Sorry if this isn't exactly the right spot, but the Nissan section gets very little traffic.

I was hoping to add wideband w/ emulation into both banks of my Nissan Frontier to use with a ProLink. Unfortunately, I'm not sure it's really going to work. The first stock bung is only about 12" from the cylinder outlet, and is directly in front of the primary cat (see picture 1).

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The only location within the correct range would be in the midpipe, somewhat upstream of stock sensor 2 (see picture 2).

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I spoke to Innovative and AEM (Zeitronix has not responded). Innovative basically reiterated their install instructions, and I have read on other threads here that they have expressed dislike of using NB emulation. AEM suggested I consult an experienced tuner in regards to locating the sensor. That's where I hope someone here might chime in.

Any more-professional-than-me (which isn't much) tuners on here have experience locating this close to the exhaust or alternatively after the first cat? I found a few threads on the latter, but nothing really concrete. Would this be a waste of my time to dig farther into this? Being in MA, I can't even relocate the cat's to make everything work.

All three units I've found with NB emulation use Bosch 4.9 sensors, which are not my fav...I have always stuck with NTK in the past...am I missing a brand that might better suit my needs? If I have to go downstream of the first cat, I'll just add them as separate bungs anyway, and would probably use the Ballenger units instead.

The spot, after the 1st cat, should be fine. Those 1st "light-off" cats are overwhelmed by flow, under load. So, their effect is negligible.

The 1st position ( pre-cat ) can have very wide swings in EGT, which can cause sensor failures.

The run is short enough that the 2nd position will not cost you much, in terms of response times. Especially, with the SLOOOOWWWW NTK sensors.

As for NB simulations. I would avoid it, if possible. NB sensors are more reliable than WB sensors/controllers. Smart WB manufacturers avoid NB simulation, for liability reasons, etc. And, the NB sensors give good, reliable, "sanity-check" data.

Advice I can work with, thank you. I have no issue installing new bungs in that mid-pipe...I just wanted to know the pre-cat wasn't going to muff everything up if I went that route.

You would get more error from the temperature swings, in the pre-cat position, than you would get, from the catalyst function, even at idle/light-cruise, in the post-cat position.

The calibration of WB sensors is only valid at their operating temperature point. So, big swings in EGT, impress on the signal, until the controller can compensate for them, by modulating the sensor's heater. And, obviously, if the EGT exceeds the calibrated operating temperature, there is nothing the controller can do, but turn the heater off, completely; and, wait for EGT come back down into a working range.

That happens allot, when close to the exhaust ports; especially, with retarded timing. i.e. if you see the headers glowing, you probably do not want to put a WB sensor in them :)

I can't imagine my little truck V6 ever getting that hot...I'm only looking to tune it because I already owned HP Tuners, and why not tune all the things...

I see a lot of people using bung spacers and things to reduce heat, but I can't imagine that is any more accurate than being downstream. Plus the midpipe is 1.2M times easier to access for welding.

Although I have headers to go in...I may bung one first, and try a before and after the cat for a short stint. $50 to add one bung to see what the real difference might be could be an interesting test.

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I see a lot of people using bung spacers and things to reduce heat, but I can't imagine that is any more accurate than being downstream. Plus the midpipe is 1.2M times easier to access for welding.

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That's a tough call. Some controllers do a better job of regulating sensor temperature than others, when EGTs change quickly. So, for those slower controllers, adding thermal mass, via a bung extender, to slow down the temperature swings can help, quite a bit. The Innovate HBX-1 works particularly well, for this.

But, that is more for sensor life, than asccuracy.