Hey I have never seen or had any asked about this, but I figured I would check with everyone. Is there any reason why it would mater of the wideband is pre or post turbo? I wouldnt see why it would make a differece, but didnt know for sure. I have it setup this way for the FAST XFI system and I also have another wideband setup after the turbo in the downpipe and they show a little different numbers.

Anyways if I could get your thoughts on it that would be great.

Thanks
Jeremy

 

If you can put it after the turbo. Most people put it about 12-18" from the outlet. The manual for my LC-1 says that before the turbo there can be a lot of pressure and that screws up the reading for some reason. I think it said something about heat too.

 

Put it after the turbo, and be sure there is at least 1 foot between the turbo and the sensor. They do not like high bung temperatures. I screwed mine into the bung I welded in for the factory sensor (6 inches after the turbing), and it lasted 2 WOT pulls. Now I have it 3 feet downstreem and it has lasted months continuously.

 

The bosch sensor that came with my lc-1 is supposed to be good to like 900 degrees, but I don't really believe that. They reccomend in the manual to put a heat sink on it if you think it may get too hot. All you do is cut like a 4" square out of a sheet of copper, drill a hole in it the size of the sensor, and just kinda roll it up around the sensor to dissipate heat.

 

Well the car has a cartech kit currently on the car and the wideband is currently about 5 inches from the turbo. So far the sensor seems to be working correctly, but I have no way of being 100%. I think I will create another bung on the downpipe and mount it there.

Any other opinions are more than welcome

Jeremy

 

+1 on the teperature point, one of the challenges in making a accurate sensor is creating a correction table to compensate for temperature differences.

 

What about the wastgate??? if it comes into the downpipe where the sensor is -- can that be a problem??? On my set up 8-14" is right where the wategate comes in. After that, it is going to have to be by the trans b/c there is no where else i can get to.

 

I would run stock O2s before the turbo, and WBO2s after the turbo. Like someone said, pressure can shift the readings of a WBO2.

 

I had mine before the turbo and when not under boost it would work just fine, but when you put boost to it
it would show lean real fast. Put it in the downpipe and it works fine now.

 

Humm, It appears if it is registering A/f Correctly and I have made a couple pulls and a/f is around 11.5 on the fast. I am still considering moving the 02 sensor to the downpipe near the same point I have my other wideband sensor just to be on the safe side and keep it away from some of the heat.

Jeremy

 

The biggest issue with running the O2 sensor before the turbo is the backpressure not the temp. The o2 sensor is always sampling 02 from the air surrounding it. If it can't sample the air because of the large positive pressure in the pipes than the accuracy is lost. Not a good thing.

 

This week I am going to relocate the sensor on the downpipe, next to where I have my other wideband 02 sensor mounted. I am not sure why they decided to mount it there, but I definetly dont want to take any changes.

Jeremy

 

from this website:

http://wbo2.com/lsu/default.htm

" Sensors should be placed so they are not overheated (gas temp not above 750 °C,
nor cooled beyond the ability of the heater to maintain their working temperature (~10 Watts). "

750C =1382F

Pretty easy to go over that on a hard run if too close to the turbo