Cats attached to the headers reminds me of the way cats were situated on my ZR-1. If true, you will not be able to legally run long tube headers on the new Z
When I modified my ZR-1, I did exchange the header-cats for a set of long tube headers with two cats further downstream. Unfortunately, the car could no longer pass emissions because the cats were now too far downstream to significantly light off...
Just a thought...
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'08 Atomic Orange Z06 with 3 LZ Sienna Wrap Interior, Nav, and Chromies. M2W, Halltech Killer Bee, Air Charger, 180 degree thermo, Body Colored Spoiler, More Mods coming