Gonna install some headers...cats, or no cats? How much louder will headers make the car with cats/without cats?

 

It will be louder with headers no matter what. Obviously louder without cats. I would not have cats if you don't need to pass emissions, whats the use of having them. If you do have to pass emssions, keep them on.

 

Honestly, I just installed SLP's on my car and I already had Magnaflow catback...It didnt make it that much lounder because I still have my stock Y-pipe. It did clean up the sound and ..uhh...a lot more power.....

 

But how well do the LS1's handle no cats? Do you know anyone that sells the 2 3/4 tube to fit between the headers and y-pipe?

 

Im not sure how they sound but if you plan on not having cats just buy the off road y pipe.