I have a 96 z28 that has two cat's and four O2 sensors, correct me if I am wrong but are the first sensors that are before the cats for calculating fuel adjustments, and the sensors that are after the cats just for making sure the cats are working right? Also can I remove a cat or will this make my car run like crap since I have an O2 sensor behind it? I am running BBK shorties due to the fact my car is lowered and I want it to be a little louder but am afraid if I remove both cats they will be to loud because I do not have my mufflers on. Thanks for the help.

 

You are correct. For the most part if you remove the cats all you iwll get is a ses light. I think it might sound strange with one cat removed. IT will also cause a difference in power among cylinders. I don't recommend only doing one. Either do both at the same time or just one.

 

I'd remove them both, the above guy is correct, only taking off one will create a slight imbalance on the cylinder banks. The SES light can easily be taken care of by either having the codes deleted out of the PCM (PCMS4LESS or Madz28) or using a pair of 02 simulators that can be purchased from Thunderracing, Summit, or Jegs.