I am about to install some headers in my L03... I've heard of fake O2 sensors so you dont have to mess with adding and drilling a bung for the O2 sensor to go into....Are fake O2 sensors worth looking into?

 

... They're probably buildable anyway, just a resistor or something like that?

 

If you're leaving the TBI there, you're going to need it... the ECM won't know what to do without it, specifically it won't know how much fuel to meter.... it needs to know how rich or lean the engine is running, to make a decision on what to do next

 

Yeah thats what I figured.

 

A lot of imports that use O2 sensors before and after the cat converter have a hissy fit if you remove the cat. That's primarily why the "fake" O2 sensors are made; to put them after where the cat was.

I suppose some of the newer American cars have the same setup, but not 3rd gens.