Best place for WB O2 sensor on a V8?

[PJF]

Hi all-

I have a Ford 4.6L V8 being run by an MSII. Until recently it was turbocharged but I have just gone back to naturally aspirated.

While turbocharged I had the O2 sensor in the turbo downpipe. Now I am fabricating a new single exhaust.

My question is this, can the O2 sensor go in either exhaust bank or would it be better to install it in the exhaust after both banks have merged so as to get readings from both banks?

Thanks for any help!

[PJF]

Hi Lance-

Thanks for the reply.

The sensor is the heated Bosch 5 wire with the Innovate LC-1 as the controller. It has worked great on the turbo application.

I am wondering though, is there going to be a big difference in O2 output from bank to bank? If so then I guess the sensor really needs be installed after the merge so it is getting readings from both banks. As you said this makes it a bit difficult in terms of installation and wiring. The LC-1 is now mounted in a very convenient location under the hood but I could move it if I needed to. But I would like to just keep it in the same spot and put the sensor in the head pipe on the drivers side. It would simplify things greatly for me.

I kind of feel that there really should be almost no difference in O2 output from bank to bank so just having O2 readings from four cylinders should be fine, but if it would be better to get the readings from all eight cylinders than I will put the sensor in after the merge.

Any thoughts are welcome!

[Matt Cramer]

Putting it on one side should be fine. While there are some problems this won't tip you off to, there isn't likely to be a huge difference side to side.

[PJF]

Thanks Matt!

That is what I had figured but I am glad you could confirm it.