Thread: Exhaust problems ugh

Hi guys..let me give ya a run down of the car. B13, WAI, (just got) obx header w/downpipe. Stock cat and exhaust. Ok so here is my problem, since Ive put on the header I cant seem to keep the manifold gasket from leaking under 1/2 throttle or more. It sqeekslike a dying monkey lol. But not noticeable under normal cruising or idle? I did notice my cat was missing most of its inside guts. I didnt bust it out. Is it possible my stock exhaust is clogged and causing this? Any help is grateful!