Hey guys, its about time for me to weld in my o2 sensor bungs but im not sure where i should mount them? Any ideas and pictures if available would help!
Are you running headers or manifolds? O2 sensors need to be mounted in the collector or right at the beginning of the head pipe coming off the iron manifold. This way they get all 4 cylinders. The closer to the head, the more accurate they are, but the length of the header/manifold has to change to get it closer/further from the head. This is one reason LT headers are not emission legal... the collector is too far from the head for the O2 sensor to be accurate.
I have a fuel injected 5.0l and I welded my bungs in the collectors. Tilt slightly upward to protect them from road debris but make sure they are in the collector at a right angle is best for sampling. Also make sure you use heated O2 sensors so that you don't have to rely on exhaust heat. My set up has 40,160 miles since the conversion with virtually no running problems and about 20-25mpg.
I usually put them right where ratio has posted, only difference is I try and get them more at the 10 to 11 o'clock position.
