welcome to exhaust leaks...i still have my shitty exhaust leak, doesn't seem much can be done. i finally found out where my leak is coming from but can't find a way to fix it...the welding on the flanges was done a bit poorly on this hotshot header...i bought some lock washers and well if i tighten it...it's perfect for 2-3 days but then gets loose again. I tried using this copper gasket seal shit but it just burned off...i've been looking for a high tempature one but can't seem to find one...something u just have to live with...I MIGHT just have those fuckers welded by a mechanic.