3.6 Wideband sensor location

[Bullfighter]

Wideband O2 sensor should be before the cat for best accuracy. After the cat can still be useful for full-throttle tuning because the amount of O2 used up by the cat is very small compared to the amount of exhaust flow at full throttle. At part throttle, the cat would affect downstream O2 readings more.

Thanks Pickles, I know you run a turbo so I know you have a lot of knowledge on the exhaust manifold etc but where do you see room to put the bung before the cat? Hell if there is room for the bung I still gotta drill a hole and weld It in and it is tight. Thanks I appriciate your help and knowledge.