I need to dial in my carb and want to use a wideband O2 sensor as a diagnostic device. The sensor only needs to mount temporarily. Since the car has 3" exhaust with cutouts, I ordered a set of header reducers and a walker 2.5" pipe with an O2 bung pre-installed. The other option was a unit that mounts an O2 in the tailpipe but I figure the cutouts get me closer to the engine.

The plan was to hook up the O2 to a basic multimeter, which would work for narrowband but apparently not for the wideband. So, back to the drawing board. I'm searching online for a cheap wideband gauge but that isn't going so well. The least expensive seems to be the AEM 30-4110 at around $170, which I have a hard time justifying. I'm thinking there HAS to be a super cheap way to link the O2 to either my phone or a laptop with basic freeware that will give me a digital AFR readout.

Again, this is a temporary, less than ideal hook up for the sake of having an extra layer of feedback for carb tuning. I know very little about oxygen sensors or electronics so whatever you suggest will have to be simple to operate. I'd like to use a LSU 4.9 sensor, which seems to be the standard in 2023. From what I've read, the 4.2s need to be calibrated, while the 4.9s do not.

Thanks