Hello! I just purchased the Madness V2 headers and I have been searching all over google for the answer to this question. Can I keep the stock catalytic converter on the exhaust system to pass emissions tests if I have the V2 headers installed? Thanks

 

Yes, I believe that's what the spare flanges are for. You will need to cut the cat out and weld the flanges to it, as well as cut out the test pipe on the header.