So I put on new headers and dc up pipe on my 10 wrx premium. I didn't use all new gaskets because I thought if I am not replacing certain parts it would be ok with the old gasket. But now I have an exhaust leak so I need to take off new headers and up pipe. But do i need to torque the exhaust parts down to a certain lb. Or just tighten it up. I'm going to go buy new gaskets today so any help is appreciated thanks.