lets say you have a dual cat car, cut the Y pipe behind the two cats, and run duals back, would this make a difference?

Also, would swapping out the single cat Y for the dual cat Y have negative effects?

 

No cats will adversely effect your emmisions levels.

A "True Dual" exhaust is a moot point on a 3.1 though. But I'm sure you're tired of hearing that kinda thing..

I cannot possibly see how a different exhaust behind the cat would affect emmisions, just exhaust tone and flow.

If you can find an N10 dual cat setup, you are taking a risk, cats start to go downhill at around 50K miles, so you may be buying a 200K ruined cat setup and your emmisions will suffer. Plus, I belive it's illegal to buy used catalytic converters.

 

thanks for the reply, I;m trading offthe 3.1 for an LT1 camaro(or a 3800 series II if I cant afford the V8) in the few months, so I was asking because I want duals on it. I guess pulling everything from the manifolds back should be ok as long as you used cats and put them in the factory locations.

 

It wont affect it.