Single turbo o2 sensor setup
 

I have a 5.3 with a single turbo. I’m running the Hooker Turbo LS manifold set with crossover pipe. Anyone familiar with the passenger side manifold, there is a 3” vband flange. That feeds my turbo. From the turbo I’m running a 3” downpipe. About 20” down the pipe is the o2 sensor. I’m running one... I’m also running a SD tune. Does this sound about right or normal? I’m worried about running an O2 right off the manifold pre turbo..

any input put would be great.

I have my o2s plumbed pre-turbo. I've seen a lot of setups like that but have also heard that you can cook them and they should be placed into the downpipe.

Pressure skews the wideband feedback, not a small amount. Leave it where it is

stock narrow band O2's in each header, wideband sensor in the downpipe at least 1ft away from the turbine outlet. No issues.

https://cimg9.ibsrv.net/gimg/ls1tech...dc350c0f3.jpeg
This is the turbo piping I’m running. I could throw one in the cross over pipe to read the driver side bank but on the passenger side due to it being cast iron.. and the D side feeds into the P side manifold and the merge at the front

same here

I ran a narrow band in each manifold pre turbo and my wideband about 12 inchs behind the turbo. No failures for 40,000 miles. I replaced the narrow bands awhile back thinking the pressure would have harmed them but the new ones didnt read any different at all. So in my experience pre turbo doesnt hurt a narrowband.

If you are running open loop, you are fine.
I’m assuming you aren’t trying to run closed loop with the factory O2 sensors.


Ron

Closed loop would help with non WOT drivability correct? I need to relocate the factory narrow band pre turbo it sounds like

Ive been running 1 single narrowband in my downpipe. It is wired to both sensor inputs to the pcm. Works perfect imo the closed loop fueling stays between 14.6-15.0 back and forth.

I figure I tuned it off 1 sensor in the downpipe so why not have the narrow band there too. And I only had to buy 1 sensor lol

And it will 100% help part throttle. Maybe some of the great tuners can make a VE table that's close enough year round and leave it open loop. But I just stick a narrowband in and let the pcm do it's thing

Copy that, I did not know you could wire 2 into one sensor. Makes sense! Thanks guys for the input!! I’m going to go that route (wiring 2 into 1) and the relocate the narrow band into the pre turbo pipe for a more accurate reading. And leave my wideband in the down pipe.

Supposedly pre turbo pressure will skew the o2 sensor readings. Most advise against putting them there. But I have seen guys that put their wideband pre turbo and tune like that, but then again I read wideband isn't as affected by pressure as narrowbands.

I put mine in the downpipe because of the pressure skewing. There are several threads talking about the narrowband vs pressure thing. I never put mine pre turbo so I can't comment on that