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chevynut
03-13-2015, 01:49 PM
I'm trying to figure out where the best place is to put my O2 sensor. I'm running a Holley Commander 950 PRO ECU that uses one O2 sensor and I bought a Holley Wideband upgrade kit for it that uses a Bosch sensor. The Holley instructions say to put the O2 in the header collector, right after where the tubes merge and gases mix. The problem is that way you only get one bank of cylinders that way.

I understand that if you put a normal O2 sensor too far back in the exhaust it's too cool to control the mixture at idle. But I don't think this is the case for a wideband sensor which is heated. Does it make sense to put the wideband sensor in the x-pipe? The other options are just in front of, or just behind the header collector connection point.
Rick_L
03-13-2015, 02:14 PM
Usually if you have long tube headers, the O2 sensors are put in the collector. You'd think that they'd have a way to put an O2 sensor in each bank of a V8 engine's exhaust system, but apparently they don't.
chevynut
03-13-2015, 03:36 PM
After crawling under the car again to look around, I think the best place for me to put it is in the collector extension, not the collector itself. It would be maybe 8" further back but I'm not sure that's a problem. One advantage is that it gives me more lead length on the sensor to connect to the wideband controller, which I've mounted behind my shifter near my ECU. And I can have my headers coated without messing with the sensor location. There's plenty of room beside my transmission for the sensor too. I don't know if that would be better than mounting it in the x-pipe, though. There's room there too if it's not too far back.

4199
Rick_L
03-13-2015, 04:39 PM
I don't think it's too far back, especially if it's heated.
chevynut
03-15-2015, 08:12 AM
Just realized that if I put the sensor in the x-pipe, it won't get any exhaust when the cutouts are open....don't want that. So it's either going into the collector or collector extension near the flange. I plan to put bungs in both sides, in case I decide to move it to the other side someday.
cardoc55
11-25-2015, 08:07 AM
? SEE how long the heaters stay on .
chevynut
11-25-2015, 09:18 AM
Already decided long ago that they're in the collectors. Thanks for the input. :)
WagonCrazy
11-28-2015, 08:17 PM
Did some searching for a general writeup on O2 sensor installation and found this from Bosch. Seems like good advice overall.

http://wbo2.com/lsu/LsuInstal.pdf
chevynut
11-29-2015, 05:37 AM
Good stuff Paul, thanks!
Rick_L
11-29-2015, 08:59 AM
? SEE how long the heaters stay on .

Heated sensors are always on, at least they should be.
Bitchin'57
11-30-2015, 05:34 AM
You're over thinking it. Just put the wideband in the collector like Holley says to. I installed a Holley Terminator kit on my last project, and it said to install the wideband in the collector. I did, and it ran great, no issues.
chevynut
11-30-2015, 10:21 AM
You're over thinking it. Just put the wideband in the collector like Holley says to. I installed a Holley Terminator kit on my last project, and it said to install the wideband in the collector. I did, and it ran great, no issues.

As I said, that's what I already decided to do months ago. ;)
Bitchin'57
11-30-2015, 07:13 PM
As I said, that's what I already decided to do months ago. ;)
That's what happens when one skims through the replies! lol