Adding O2 to SSIs

[jpgroth]

Hello! I’m converting a ‘79 SC to EFI and need to a wideband. I’ve read various sizes on the diameter of the SSIs. Is the go to route welding in a bung? I’m not a welder and want to add an O2 bracket. Will this suffice or be too large?

https://www.boostcontroller.com/No-Weld-O2-Sensor-Mount-2-inch-p/uxnw-30-2355-200.htm

[Trackrash]

Do it right and weld in a bung. Shouldn't be that big of a job for a welder.

[aigel]

They used to come with a bung, I guess no more?

[jpgroth]

Yeah mine did not. I think I had the option when I bought but wasn’t thinking ahead to this point. Darn

[aigel]

I would buy the O2 sensor you need, take off the SSI and bring it to a good muffler shop that can weld stainless. Maybe your local Porsche independent shop. In LA, I used TRE I would make sure it is in the "stock" location.

G

[E Sully]

Position is important. I added one in the same location on my 1973 SSI's, similar to this.
https://www.pelicanparts.com/More_Info/PELSW852440.htm?pn=PEL-SW85-2440&bt=Y&fs=0&SVSVSI=
Local shop did the stainless welding.

[juanbenae]

are the SSi's off the car? if they are weld a bung in both and plug the one you decide not to use. won't devalue them at all and you have an option to monitor each bank if needed at some point.

also, if you have turbo valve covers watch where you mount it because off just a tad makes getting the cover off nearly impossible, off a bunch it will be impossible.

[OSC911]

Originally Posted by juanbenae

are the SSi's off the car? if they are weld a bung in both and plug the one you decide not to use. won't devalue them at all and you have an option to monitor each bank if needed at some point.

also, if you have turbo valve covers watch where you mount it because off just a tad makes getting the cover off nearly impossible, off a bunch it will be impossible.

I'm about to do the same - thanks for the advise re: turbo valve covers

[PhillIB]

I did as above, took SSI off, drilled hole where I wanted it, took it to a welder (with boss) and it took them 5 minutes.

[evan9eleven]

Here is how I placed mine. Purge welded with Argon so the inside would be nice as well. Its not jewellery, but then again I’m not a pro welder.

[jpgroth]

Got a welder to do it. Turned out great. Thanks for the bump to do it the right way

[911pcars]

My suggestion would have been to install on both sides. Plug the unused bung for now. Eventually, there’ll be more options for dual WB sensor circuits. Knowing the A/F on one bank is adequate, but better on both sides, especially when the fuel system uses dedicated air intake units (carbs or EFI).

Sherwood