relocation of O2 sensor???

my room mate has a 2000 gt. he just got some headers off ebay, not sure what kind they are. now the guy that he bought them off of said that he needed to relocate the O2 sensor to the cat. i looked at the headers and it seems as if there is a spot on the headers for the O2 sensor? so anyone know why he said that? and it seemed as though he had the O2 sensor on the headers. i don't know too much about eclipses, so i don't have a sure answer for him. thnx

you have to get a cat that has two threaded o2 sensor holes in it and extend the stock wires on your o2's and relocate them after the aftermarket cat. (if you have the 6 cyc w/ cali spec)

how can you tell if it is cali or fed? so your saying that he does HAVE to relocate the O2 sensor(s)? from what i heard they're are four O2 sensors? forgive me for the ?'s. i don't know eclipses that well. thnx for the help

the cali specs are more common than the fed specs. the cali has 4 o2 sensors. two directly off the where the manifolds connect to the head, and two after the smaller cats. your headers you got don't have converters connected so you can only install the two stock precat o2 sensors on the headers. the other two have to be located after the cat so you have to replace the cat with one with 2 holes after the converter and you have to extend the wires so that the o2 sensors will reach that far back.

alright i'm looking at the engine from the front and i cannot see a damn O2 sensor at all! so i am assuming that his car is FED. i will lift it tomorrow to make sure. thnx for the help.

that's where i made the mistake and got the wrong cat at first. the o2's are pretty much hidden in shields and beside the converters (which can often be missed when examining). your best bet just to confirm it is to check for the wires/wiring harnesses. just to be on the safe side oh coarse