O2 sensor question (pix)

[Michael_P]

Got a quick question:
I am doing a custom exhaust install on an older car (1981 MB 380SL). The exhaust system did not have a bung for an O2 sensor so I have to put one on. The bung I got seems a little deep. Therefore the sensor will be shallow in the pipe. As you can see in the picture with the sensor in the bung, the sensor is not fully deep. Does anyone think this could be a problem or cause a false reading creating mixture issues? I can always turn the bung down on a lathe if needed.

Thanks in advance

 

[spasm3]

Front, in the exhaust manifold, or rear?

 

[Audios]

The sensor further out of the stream means it will sample less, so it will be less accurate. Some people try to beat catalytic converter faults by spacing the sensor further out. If this is a mixture control O2, I would try to match the depth of OE.

 

[Ducked]

Not advice, because I don't know, but perhaps it would be possible to mount a piece of halved or quartered tubing in the bung to direct exhaust swirl into the recess.

I suppose it might erode the sensor, though, and might not be worth the trouble.

 

[Michael_P]

This is an upstream sensor only, pre OBDII. I planned on putting it at the tail end of the collector / y pipe where the exhaust of both cylinder banks meet. This is where the thickest metal is and it seems this would be the best place for a good sample. Most OE setups as well as top shelf aftermarket exhausts have the sensor go in deeper than when this bung would allow. Also, what Audios says is kind of what I was thinking. I can shorten the bung on a lathe in a matter of minutes.

 

[eljefino]

Lathe that puppy down!

 

[spasm3]

If its an upstream sensor, i'd expose it more. If it was a downstream on an older model( where downstream only monitors cats), i'd say its perfect!

 

[Michael_P]

The puppy just got lathed down. Thanks everyone for the advice.