I've looked at a lot of forums about the case of the ticking cobra motor. Ive had mine for about 2 days and noticed that loud god awful ticking especially when I was next to houses or a wall. When we put an X pipe on it, turns out a header stud was missing and the gaskets between the header and downpipes were shot! Turns out the passenger side gasket always goes bad according to a few tech buddies of mine. As soon as the exhaust was installed the ticking was gone. Not sure if this helps, but it seems a topic of great discussion.