LSM11 O2 sensor mounting height

[stownsen914]

I have a question about what mounting height is optimal for the LSM11 O2 sensor. I am able to find good information about where to place the O2 sensor relative to the collector and the about the vertical orientation, but I find conflicting information about how far the probe on the sensor needs to protrude into the exhaust stream. Some wideband kits come with a 1" tall bung for mounting their sensors, which I assume is to protect the sensor and prolong its life. I've also found some articles that say that extended O2 sensor mounting may lead to inaccurate readings.

So here I sit, a bit confused on the topic. Any thoughts are appreciated.

I should mention that the application in my case is for an M4 in a normally aspirated Porsche 968 road race car.

Scott

[stownsen914]

To give a little more info on this, I measured the height of the bung and of the tip of the LSM11 O2 sensor, and it looks like about 1/4" (6 mm) of the sensor tip will protrude into the exhaust pipe. Is that sufficient?

[AdamW]

For performance work most now choose to install with a taller bung to disrupt flow less. The sensor will still give correct measurement, just slower response.
OEM's will usually install with full protrusion, I assume because they want the fastest heating and fastest response for closed loop catalytic action. You can do it either way you like, you are unlikely to notice any difference in real life.