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Great write-up, saves me a lot of figuring.
Where is the best place to mount the O2 sensor itself? (M6)
Is there an available bung, or will I need to drop a pipe and engage a competent stainless steel welder?
 

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Great write-up, saves me a lot of figuring.
Where is the best place to mount the O2 sensor itself? (M6)
Is there an available bung, or will I need to drop a pipe and engage a competent stainless steel welder?
My Bosch wideband sensor recommends you mount it at around 10 degrees tilt above horizontal. Location relative to the cats (if you have them) and manifold or header exit matters too. The chances that there's a bung in just the right spot and just the right angle is slim. Never hurts to have an extra bung available. Spend the few bucks to get a dedicated and well positioned WB bung installed...JMHO.
 

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Great write-up, saves me a lot of figuring.
Where is the best place to mount the O2 sensor itself? (M6)
Is there an available bung, or will I need to drop a pipe and engage a competent stainless steel welder?
This is where I mounted mine.

 
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Thank you TriTexan and UptownV.
Looks like the only way I'm going to accomplish that is to drop the pipe and bring it to my friendly muffler shop.
 

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Thank you TriTexan and UptownV.
Looks like the only way I'm going to accomplish that is to drop the pipe and bring it to my friendly muffler shop.
I think you can get away without dropping the pipe. Drill the pipe in the right location, weld the bung in place then plug the sensor in.

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I think you can get away without dropping the pipe. Drill the pipe in the right location, weld the bung in place then plug the sensor in.

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really hard to cut and weld with the sensor in the correct postion between 10 and 2 on the pipe. I had a shop do mine without dropping the pipe and they had to weld it on the bottom side of the pipe, its not great for the sensor but I bought new cat delete pipes with a location on the top now.
 

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really hard to cut and weld with the sensor in the correct postion between 10 and 2 on the pipe. I had a shop do mine without dropping the pipe and they had to weld it on the bottom side of the pipe, its not great for the sensor but I bought new cat delete pipes with a location on the top now.
I see what you mean. Is it that difficult to drop the front pipe?

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Has anyone tried using the wiring passthrough tube thingie in the right side of the firewall by the PCM instead of routing through the doorjamb?

(I'm mounting the bung in the DRIVER'S side downpipe, there's a spot that will get the sensor to sit above horizontal, have dropped cat to weld in, will post pic when done.)
 

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Here's what my left cat with bung welded in looks like. Milwaukee #4 step drill made a perfect interference fit for the 7/8" step in the bung. Stainless bung and plug must be ordered separately, at least when ordering an AFR500 which comes with mild steel otherwise.
Rich's Auto, my local dyno and LSx-modder-maniac garage in Boise, did a beautiful weld.
 

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Most are recommending that the bung be on the passenger side due to that side running lean when it actually happens. Earlier detection I guess.
 
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Most are recommending that the bung be on the passenger side due to that side running lean when it actually happens. Earlier detection I guess.
That's what I did with my but made a fkn blunder by installing it AFTER the cat. :( I'm going to remedy it by getting headers :D

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Most are recommending that the bung be on the passenger side due to that side running lean when it actually happens. Earlier detection I guess.
Thanks for pointing that out, jeez I wish I knew that before. I have a second bung, car's in the air still, I have time...

By "when it happens" what's the circumstance? Is there a thread on that?

So if it's going to run out of fuel from too much demand for the fuel system, the pressure drop happens on the right rail first?

I'm at "Stage <1" just a Mamo LS7 TB and gutted airbox base, getting my bearings as to airflow v lambda, in anticipation of a 2.55 pulley, so gosh I hope I'm a very long way from the 700hp system wall that has been cited.

Thanks very much. This board continues to amaze me as to its resourcefulness.
 

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Many things can cause it to go lean such as bad O2 sensors, low FP, or because of a tune that needs tweaking. I honestly don't know why the passenger side has a higher incidence of going lean over the left bank. I've read of engine teardowns that cite #7 or #8 as the pot that let go bc of lean conditions. Is it the furthest point on the rail?
 

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It's a return less system that's feeds the driver side rail first be my guess
 

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Can u post pic of running wires thru dash to get to ash tray
I was going to ask how to disassemble the console or center stack without butchering it, so as to nicely cut up the cig pack holder to fit the head unit. Turns out the current afr500 is 1/4" too wide to just slip in like the thread author's unit did, so more surgery is indicated than dremel-in-place.
I should also remove my suggestion of using the grommet near the ECM as a pass through for wires: it does not have enough space in it to allow the wires to fit through. The author's original through door jamb grommet method was just fine in the end.
Until I can fit my afr500's head unit into the cig pack area cleanly, it is relegated to a velcro strip on the kick panel under the glove box. Which is okay, since my goal is its analog output for data logging more than seeing a maddening flux of 7-segments feeding unactionabe real-time info.
 

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Google how to remove center stack cts v, there are how to videos on you tube and very easy to do.
 
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Thx for posting this! Getting ready to wire my wideband this week have my new gauge mount project in the final phase! This is going to be a great help.



 
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