I will be installing Wide Band in my car soon and need opinions as to where to weld in the bung for the 02 sensor. The instructions say 18" from the exhaust port or at least 36" if running race fuel ( which I do). My question is since I am going to up my exhaust to 3" can I put the bung in the pipe just after the header or will that be too far away and better in the header?? Thanks!! Greg

Think it's like 8 to 10 inches from the collector.

I had mine welded in on the head pipe side going towards the rear of the car right at the collector flange with a full length 3.0 inch exhaust system with straight through muffs mounted at the rear bumper behind the rear end
I ended up making it a dual wide ban system later so I could read both sides at the same time before adding the hardware and software to read both sides I would swap the O2 sensor from side to side
My message is do it once and do it correct with both sides working from the start

It needs to be 18" or more from the port so the sensor doesn't get cremated and at least that far from the open end of the exhaust system so that any reversion doesn't draw outside air past it causing a false reading. It should function properly anywhere between those 2 points.

Make sure you mount it between 10 and 2 o'clock so any condensation can run out of the sensor.

If you mount it downstream from the header it is critical for the system to be air tight upstream to insure accurate readings. Any header or collector gasket leaks can suck outside air that will give you a false lean reading.


Kevin

I installed mine about 3-4 inches past the collector in the exhaust pipe, I have ran pump gas, cam 2, and about 30 gallons of100ll av gas and it has worked great so far

This is how I did mine..........8-10" past the MERGE not the flange where the exhaust bolts up to unless you have race headers then no flange of course...........

More room on the passenger side. No shifter or kickdown linkages, no cooler lines.

Kevin

Exactly for a single read unit........

Thanks everyone for the info.