Where would you add a second bung for WBO2 on Dansk Premuffler

[FA-18C]

I have a Dansk pre-muffler with the factory bung installed per the photo, and want to add a 2nd for install of a wideband O2 sensor to feed my John Bell custom AFR triple gauge.

My initial thoughts are to move about an inch toward the end and offset an inch down from the existing to preclude flow obstruction etc... Having said that, I am certain someone here has done this and likely has the best solution in hand.

Why am I doing this? I want to be able to retain the O2 sensor input to the DME, and will use the WBO2 to monitor AFR. While some recommend removing the O2 sensor by the bypass as they do in Euro cars, I am also installing a Steve Wong chip and understand the recommendation there is to retain the O2 input after adjusting idle AFR after install.

As always, I welcome input from the 911 Borg collective, good idea, bad idea, or corrections are valued.

[famoroso]

I don't have any guidance for adding an O2 bung, but...

Some WBO2s provide an additional narrowband output. My PLX does. Perhaps yours does too and you can take advantage of it?

[FA-18C]

Hey Frank, was actually going to PM you. I bought the AEM controller since Joh Bell was building me a custom triple gauge. Spent some time on the phone with icarp and he has some great recommendations. The issue is that the DME input needs to be 0-1V, but my controller analog output for the dash gauge is 0-5V. I am also installing Steve Wong's chip, which as I understand he recommends running closed loop after adjusting the idle AFR following install, then reconnecting the existing O2 sensor. So - I will just have my welder out back weld in the bung so that I can accommodate both sensors. Also simplifies install and wiring - leave the current O2 sensor harness in place and screw in the sensor, then run the harness for the AEM WBO2 and screw that into the 2nd bung. This saves me from running wires back from the controller to the OEM O2 input, or figuring out tying into the DME. This is less elegant, but sometimes Fred Flinstone works, right?

Would have tackled this weekend but appears my clutch master cylinder crapped out, so it was flat bedded from the side of the road to local independent shop. Hoping to tackle this next weekend.