O2 sensor cat bypass?

[SMC]

Do I need to run an O2 sensor on an 1988 3.2 911, with a cat bypass?

[Don Plumley]

If you have a stock DME, yes. If you have some other engine management system, unknown.

Most good cat bypass pipes have an O2 bung hole.

[PatrickB]

It'll run without it, but you'll see about a 20% drop in fuel economy....

[Boxer 6]

Originally posted by SMC
Do I need to run an O2 sensor on an 1988 3.2 911, with a cat bypass?

No you do not need to run an O2 sensor (the car will run), BUT, the car will run very rich and you will not pass your smog test. Definitely not the optimum

[fuelie600]

You can buy the bung (fitting) for about $10 from an auto parts store and weld it in. It takes a few calls to find a place that has them, but they are available.

[PatrickB]

SMC~

Don't know if you've purchased it yet, but you can opt for the bypass that has the bung hole in it already. Mine has one...

I can't believe I just said "bung hole."

[ThePointman]

I just couldn't resist getting in on all this "bung hole" chat ...
Hey, he said "Bung Hole!" LMAO