Wideband sensor and bung sizes

Bosch Wideband. What is the recommended size bung?

I've about 20 of these innovate AFR LC2 units I got cheap on ebay. They have 1" bungs with them

I have a big bag of bungs I bought on Ebay which are much smaller, maybe 1/4 inch.

Q1. What difference does it make to the AFR reading depending on the bung size?

Q2. Other than The temp of the sensor is there any issue with the smaller bungs?

Q3. How far from the flowing gasses can the sensor be before it effects readings?

I tend to install bungs on cars I am tuning (normally old stuff) and I was considering creating some king of adapter to install in the O2 sensor socket in order to take a tap off for the 5 Gas Analyser and possible also putting a temp sensor. But I don't want to waste my time if it wont work.

I could I suppose allow a flow of gas over the O2 sensor and then out to the Analyser (I was going to cool the gas also before it went in to the analyser)

I tend to not bother with putting the O2 sensors up the exhaust as the readings, esp at low RPM are always off.

Any thoughts.

thanks

Damien

Bosch recommends a minimum height of the bung of 10.5mm and that the sensor tip is in the airstream, away from the wall of the exhaust pipe so that it is not in the boundary layer airflow. A mount that is 25mm long will rely on eddy current flow to bring the exhaust gases into contact with the sensor, so may not react as quickly or accurately as a properly installed sensor.