For starters I searched the forum and couldn’t find exactly what I needed to know before posting. I’ve gutted my stock headers and of course I’m getting codes for it. I was told I need to put spacers on my downstream O2s but my question is what kind of spacers do I need? Are they only needed on the downstream sensors and do I only need one spacer per sensor? If someone could point me in the right direction so I can get rid of those codes and stop my car from running rich or lean that would be awesome.