header: 4-2-1 1-piece SS DC Sports
car: 2001 GSR

i just installed a new header on my car and have a small leak between the header and the catalytic converter. i originally re-used the donut gasket that goes between them and thought that might be the problem. i replaced the gasket with a brand new one and the leak is still there in the same spot (the top part of the gasket. between the cat/header and the underbody of the car). i tried playing with the alignment of the connection also and it didn't help.

any suggestions of what might be wrong?

i think i am just going to use a sealant around the gasket to fix the leak. does anyone have any suggestions as to what sealant to use?

any help would be appreciated.