O2 sensor (wideband) custom location (an answer, not a question)

[Frank818]

I was looking for something and thought I would share my answer.

For those in need of a custom wideband O2 location, for whatever reason, on a turbo application generally you have to mount the O2 after the turbo, say a couple of inches after for optimum readings.

Before the turbo you may run into 2 problems, the high exhaust pressure pre-turbo may interfere with the readings and high exhaust temps may damage the sensor. I thought the temps were higher after the turbo but maybe not.

Obviously the goal is usually as close as the exhaust ports but after the turbo. I think 6in to 16in after the exhaust ports (post-turbo) is best.

But, to be really sure of your installation, check with your O2 provider/manufacturer what they recommend. It may vary depending on the type of sensor for your custom application.

[freds]

Innovate list two Criteria:
1. Should be about 24" from the turbo (I don't remember exactly). So that it doesn't get too hot.
2. It should be before the Cat (if you have one)

If you can't satisfy both criteria and have to be closer to the turbo, they suggest protecting the sensor with a heat sink adapter. Theirs is expensive! The one I chose to use (just in case) is a Dorman identical clone for about $60.

I posted about this some time ago and a number of members said (in effect) that they had been running them close to the turbo without a heat sink adapter and the sensors had not had unusual or early failures.

I chose to be conservative!

fred28957

[Scargo]

Cobb and copy-cats, etc. seem to put it just before the bend on the downpipe. That is about 3 or so inches from the turbine outlet.