Guys, Does anyone know any definitive way you can test your cat to see if it's flowing like it should? Could symptoms of the increased back pressure on a stock BF XR6T be; 4 psi peak boost pressure? (im assuming this is 1 or 2 psi off the stock figure)Occasional pinging?These are the symptoms I have experienced, and I'm thinking it could be an exhaust restriction problem... Have looked at boost and manifold leaks and apparently AFRs are within what's normal... How can I rule out a cat converter problem?