O2 sensor location

[Fitz24]

Installing a Howell TBI which many on here seem to run or have run. I am running long tube headers and have the heated 02 sensor with the TBI kit. Which side and where on the header has been the best location to install the O2 sensor?

 

[DirtDonk]

So this is set up for a single sensor? Are you running a single or dual exhaust?
Seems to me that, optimally, you'd want it where the two sides meet. Ideally for some setups, you want the sensors closer to where the exhaust exits the engine (at the exhaust ports), but that's not really an option on long-tube headers, as you have to have the sensors where the collector starts.
With only a single though, I'd think you'd want it where the duals become a single.

If that's not an option, with your single unit you'd still want it in the header collector, as close to the beginning as possible. In this orientation, it only reads one side of the engine of course, but at least when everything is working properly, your system should still be reasonably consistent.
Or would it?

To those that really know, does the O2 sensor have to read all 8 cylinders, or is it just reading a ratio? Seems like that's correct, and you can have it read one bank and still keep the engine purring smoothly, but I'm not sure.

Good luck. Interested to hear what others say.

Paul

 

[JohnJohn]

I bought two O2 bungs from Summit and welded them just after the collector on my long tube headers. One on each side. You will want to get the longer wire O2 sensors. Check the fordfuelinjection.com site for part numbers.

 

[Broncobowsher]

It is a little crude, but just measure one bank and let the other go unmetered. It will be fine. I ran 7 or 8 years that way. By the time you average 4 cylinders on one side of the engine, the 4 on the other side won't change that average enough to matter. You will likely get more error by mounting the sensor so far downstream (where both banks merge) then what you would gain.

I recall some of the older Ford EFI setup that had a single O2 sensor in the drivers manifold and none in the passenger.

But with that said, you do want an average of more then 1 cylinder. So the collector is a very good spot. I know you said it was a heated sensor, but it still needs to be somewhat close to the engine to get full heat.

Since you asked about location, top of the pipe pointing down is best. but putting it in from the side is also acceptable. What you don't want is to put it in from the bottom pointing up. When the engine shuts down the exhaust is full of water vapor (water and CO2 should be the primary exhaust components). As the exhaust cools the water collects in the bottom of the pipe. You don't want the water collecting in the sensor, that kills them.

 

[jw0747]

call Howell and ask the experts if it doesn't describe location in the written directions.

 

[akforsyth]

How about something like these:

 

[Fitz24]

Thanks everyone.

I was hoping someone who has installed a Howell system could tell me if the wiring harness worked best if the O2 was mounted on the right or left side. I want to drive it to a shop and have them install it before I get started.

 

[TBS-POPS]

I have a Howell set up and it doesnt matter which side the o2 senser is on. the bung should be in the tube adapter right behind the collector of your headder. mine is on the pass side so the wiring is where i wanted it.

 

[Fitz24]

I have a Howell set up and it doesnt matter which side the o2 senser is on. the bung should be in the tube adapter right behind the collector of your headder. mine is on the pass side so the wiring is where i wanted it.

Thanks. Any reason to put it in the adapter behind the collector or can it be put in the collector of the header?

Also, what temp thermostat are you running? I don't remember reading anything in the instructions about what the computer needs to consider norm operation temp.

 

[itsabronco]

i put both of mine in the headers. I did a bit of comparing and asking a ton of questions and the distance before collector flange and after is not great enough to make any difference. works fine. one thing to keep in mind is , we are not working on precision tuned machines here, they are off road tanks !! dont over think it, get it done, and enjoy your ride !

 

[TBS-POPS]

Thanks. Any reason to put it in the adapter behind the collector or can it be put in the collector of the header?

Also, what temp thermostat are you running? I don't remember reading anything in the instructions about what the computer needs to consider norm operation temp.

In the adaptor behind the collector will even out the reading and wont be so apt to pick up the gasses from 1 cyl. 180* thermostat is fine.