O2 sensor placement

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umwtnt

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88 RCSB with 5.7, I'm fixing to replace my Y pipe with a JBA Y pipe. I have shortie headers and the current stock O2 sensor is installed in the left side header. I also have a high flow cat already installed. I have ordered the GM AFS74 heated oxygen sensor and harness and I'm debating on whether to install the O2 sensor in the stock position OR install it in the JBA Y pipe. I feel that the sensor would get a better reading of the exhaust at that location then just in the left side location. Anyone with thoughts on this? Engine is a reman with app. 10000 miles on it, Summit 1101 cam and shortie headers. I also rebuilt the transmission in it when I replaced the engine. Getting ready to do a 4/6 drop on it and install a posi with 3:73 gearing, currently 3:08. Just making changes a little at a time. Also, I have read 100's of post on this site and the knowledge I have gained is tremendous, THANK YOU everyone.

 

PlayingWithTBI

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I'm debating on whether to install the O2 sensor in the stock position OR install it in the JBA Y pipe. I feel that the sensor would get a better reading of the exhaust at that location then just in the left side location. Anyone with thoughts on this?
Sometimes you get a problem with engine surging from the O2 sensor being too far from the exhaust valves. Then you have to play with delay, in the calibration, for the ECM to respond from O2 input. The advantage of getting feedback from both banks is minimal unless you have a miss fire or other issue(s) from the right bank. I'd leave it in the header, if it were me.
 

umwtnt

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A short follow up, I took Playing with TBI's advice and everything went well. It even got rid of my slight surge. What I did find though was a good point for a 12 volt switched circuit. I had already done the NBS master cylinder sway and removed my ABS. In the ABS plug there are several switched 12 volt circuits. I used one of them to power my 3 wire O2 circuit along with the ground on the plug and it works wonderful. Thanks for the advice.
 

Treble

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umwtnt.....Can you post up a few images of how you tapped into your ABS plug. I have the same O2 sensor. And have done the ABS delete.

You were able to use the ABS plug for both power and ground?
 

umwtnt

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umwtnt.....Can you post up a few images of how you tapped into your ABS plug. I have the same O2 sensor. And have done the ABS delete.

You were able to use the ABS plug for both power and ground?
After I removed the ABS box all I did was test each wire for power and ground. Switch on and off. If I remember correctly I found 2 hot wires and 1 ground. I wired the O2 sensor using the switched hot wire and have had no issues. Everything is taped up so it would do no good to take any pictures. I hope this helps.
 
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