After a little advice/info/help on wideband sensors please! As I'm starting to doubt what I've read lol

So I have an S5 Turbo II Vert. I'm fitting an RB REVII turbo back exhaust, I've also fitted 750cc secondary injectors, an Aeromotive Stealth and will be fitting an Rtek 1.7 chip shortly.

I've also got myself an AEM Digital Wideband sensor/gauge to keep track of what my AFR is doing.


Currently the RB downpipe has one boss on it for an O2 sensor near the top of the bend. My plan was to put a standard narrowband sensor here to keep the ECU happy etc. then I'd get a second boss welded in further down for the wideband to run the gauge.

But having a read through of the AEM instructions, the wideband sensor can emulate a narrowband.

So.

Could I put the wideband sensor in the downpipe, and set the output to emulate narrowband to keep the car running happily? (Would it still display the proper AFR values on the gauge?)

The issue I can see with this though is that it would be quite a lot nearer the turbo than AEM recommend so I might be at risk of just killing off the sensor?

I think I'm leaning to fitting two separate bosses and sensors just to do it properly but was interested to hear what others have done

 

Innovate sells a wideband heat sink that works pretty well.

You can also make your own out of copper sheet.


That bring said... Welding another bung down stream is the correct way to do it.

 

I second welding a bung for the wideband farther on the downpipe. Rotary EGTs are truly impressive and will cook the sensor if too close to the turbo. More than once I've seen widebands "stall" when making pulls and not work again until cooled down. At that point can the sensor be trusted again?

The narrowband output will work fine for the stock ECU/RTek. Just make sure you have it on the correct emulation. Some emulate it linearly, which is way wrong for the Nernst cell in the RX-7.

 

Do the bung at the end of the downpipe. Just make sure there is clearance. My sensor hit my transmission mount, so I ground a hole in the mount. That also worked. In the future, I'd go closer to level instead of trying to get the sensor pointed upwards.

 

Cheers for the replies guys, I think I'll do it the proper way as you say and get the second bung put in further down

I think I was just trying to be lazy and avoid the little bit of faff of putting the downpipe in place and marking it to make sure I had clearance before getting the bung welded in as I can't do it myself lol