I'm replacing my short headers with long tubes and i plan on running a dual cat set up. Im worried about not having enough room for both of my carsound cats near the Y-pipe. I was wondering if the following was possible and would still pass the CA sniffer -

Since i have true duals, could I just place each cat towards the very rear of the exhaust after the X-pipe somwhere, right before each tailpipe even? Then I would simply use o2 sims for the rear o2 sensors. Anyone follow what I'm saying? I know I wouldnt pass visual, but with long tubes i wouldn't pass visual anyway. Any thoughts would be great.

 

Nope! It won't work. In order to work the cats have to stay above a certian internal temp. They have to be placed as close to the headers as possible. I'd say within a foot at the most.

 

ahhh booo