Passenger side 12 o'clock position about even with the front edge of the door. So its easy to run into the car because there is a grommet just underneath of the seat that will allow access for the wiring.
but when my car was N/A it was on the passenger side in the H pipe, try and keep it aas close to the headers as possible while still having easy access to it
yeah for wide ban. why only one? is it cause the price of the WB O2's? i would think that you would want one on each side so you can see what that bank is doing.
Generally speaking…it seems that the extra price does not justify the benefits (unless you can tune each bank individually). I do believe that the left bank is the one which will typically run lean first anyways. If you plumb the wideband to the lean bank, the other will only run slightly richer (more safe).
mine is in the x pipe just behind the collector on the driver's side, I didn't want to drill a hole in my longtubes, so that's where I put it seems to work fine.