where they the sameones like on ebay

 

The rear o2 sensors have nothing to do with how your truck runs.....period. The front o2's are what make your AFR's right. The rear o2s are only there to make sure the cats are working. You will get a CEL but thats it.

 

he is right

 

PLUG DEFOULERS FTMFW
Ran them 4 years with out any ses light, I laph when people say they don't work, shame on them
John

 

I would not put on the headers without tuning soon/right after. It will need tuning changes. And ya O2 sims only go on the rears sensors and have no effect on engine performance. Keeps the dummy light off.

 

haha yea i ran them for a little while on the GTO and now on the truck till it is tuned and never had a ses light

 

It wont hurt anything, but you also won't get the full performance from them alot of other people on here have ran for a long time with out a tune, I ran for over 4 years untuned, never any problems...

John

 

PM 00z71 he's a local guy that can help out with your tuning.