I am going to install an A/F gauge and would like to be able to take readings from both banks. If I were to have a small H-pipe put in between the mufflex 3" Y-pipe would the sensor get hot enough to read correctly? I know that some of you will say that there isn't room for a small pipe to connect from one side to another but I've already measured and I can make it work. It will go right behind the header collectors. The H-pipe will also have to be installed off center of the Y-pipe slightly. I may do this regardless of the sensor location.

 

The closer the O2 sensor is to the engine itself, the better it will work. IIRC, it has to get up to at least 600* to work properly. I doubt the H-pipe will get that hot.

 

also think about flow.
if you put the o2 sensor into the h-pipe I wouldn't think it would read the exhuast correctly as it would actually inside the header collector

 

I've wondered about this myself after after doing Pillsbry's v6 exhaust. The o2 on his car was at the 'Y' on his stock pipe which, seemed like a good idea in that it's reading the exhaut from all 6 cyls or the overall rich/lean of the motor.

On any of mine, it's just getting the o2 from the drivers side. This was a serious problem when I got my camaro as the 5 cyl plug wire was off. This cause the rest of the motor to run ultra lean (judging by the white electodes at leas ton the other 7 cyls).

Would, if poss., a heated o2 solve the temp. problem if mounted further from the collectors ? Do v6 exhaust temps run that much hotter that the o2 can be mounted further away as well ?