Viking with a Hammer
Oh, yeah. If the engine can compress the air in the exhaust to 200psi, and you have a 3" exhaust that's 1884 pounds of force on those header studs. My cat is about 6" across. So a blockage there can be 3768 pounds of force easy. That's why the potato trick never works.My 04 broke all studs when the manifolds warped from a plugged cat.
Clean tight bolts can handle that with no problem. But header studs aren't clean or tight.