How are people installing sensors into a jacketed header/ manifold?? I assume you'd have to cut open the coolant jacket, install the bung into the exhaust wall and somehow re-weld the coolant jacket? Sounds like a nightmare. I'm running Gil's so I assume if I installed one it should be up towards the riser where all the exhaust gases come together?

Drill a hole in your riser near the turn, weld the inner and outer together, then weld in the bung. Done.

Thanks. Just so I'm understanding clearly: are you saying drill a hole just through the outer wall and then filling the entire hole solid with weld and then drilling through that into the exhaust chamber?

I was reading into this a couple of months ago. What most I seen did was at a 90 degree angle (so right or left of manifold riser) in your case on your elbow, drill through both walls. Ping down the outer wall to meet the inner. Then weld both walls together. Following that, insert bung and weld bung to outer wall. Screw in o2 and be done. Most tried to keep this location as far upstream as possible from where the water and exhaust gases mix to try and prevent any reversion condition that could possibly result in any water touching the o2 surface yet far enough down stream to try and gain a good 4 bank average. If that makes sense.. Also if you have room I would install the sensor facing toward the motor to try and hide -Chris

there is description, forget who. drill hole thru both walls, knock outer in with ballpeen hammer and weld walls together, then insert sensor fitting and weld it in. think they leak tested before putting fitting in.

1. Call CMI, Imco... and buy a stainless weld in bung.

2. Plan where sensor will go. Never put on pottom of exhaust, it does not read well and water will always find it. Put preferably between centerline (horizontally) to top, center. Needs to be close to the flange, usually you can do this at the tailpipe which is easier to remove, but sometimes it must be at the header. Make sure where your going to put it clears everything, sensors are long and can hit if you don't plan.

3. Drill hole through (both layers).

4. Use a chamfer tool, punch or ball ping hammer and dent the outer layer of SS so its almost touching the inner wall.

5. Weld the 2 walls together (now you don't have to go weld the inside) from the outside.

6. Now weld in the bung.

Now that makes sense- thanks to all.