On a dual cat shorty header system, where is the best place to put the WBO2? I would think that at the y where both banks merge, but can widebands be placed post cat?

 

Before the cat, if it's to do any good.

 

Thats what I figured, but wanted to confirm. Thanks

 

I have mine on the y where both banks of cylinders merge. Its a heated sensor so it should be fine that far away from the engine. You want it before cat.

 

At the y pipe would be ideal so that I can pick up both banks. But with a dual cat option, the y is after the cats.

Here is another question. Should the NB and WB be on the same bank? If they are not, will I be fighting with one or the other?

 

I dont think it matters if both are on same bank as long as they are positioned right. I would stick wideband in one bank before cats. Real nice if you can get 2 bungs, one for each side and move it over to check other bank but both should be close. Unless you have serious issues with inj firing and air distribution, but you wont need a wideband to notice that

 

That is actually what I am going to do. I am going to be welding two bungs on on each bank and go between them when I tune to make sure that nothing weird is happening. I asked the question as I don't want to be tuning a lean area when the NB is reporting rich.

 

Placing the WBO2 in one bank or the other is fine. Both banks will be close on fueling, unless there are mechanical issues, which as already said, you'd notice without the WBO2 sensor.