Ladies and Gentlemen:

I have a question to see if anyone else has this issue, and if so, what they think is causing it.

So, before the installs, no rattling (gasp, I know!). I installed my perrin elh, and no uppipe initially. That resulted in a rattling noise pretty much all the time. I ended up taking off the stock uppipe (and heat shield) and installed a perrin uppipe, which solved the problem for the most part. However, when decelerating, or cruising steadily, at around 2500 rpms I get a metallic rattling noise. It's not a motor noise, but more like a heat shield noise (except I have no heat shields on the car at this point besides the cobb turbo shield and downpipe shield).

I used worm clamps to hold the heat wrap on the uppipe (which I think is rather typical), so I assumed the ends of these were hitting something initially. I cut the ends off them, and I'm still getting the same rattling noise. It could be a resonating frequency between the metal of the headers/motor/uppipe, but I'm not convinced on it, hence the post.

I'm at a bit of a loss as to what it can be at this point. I've assumed one of the connections is a bit loose on the turbo/uppipe/headers, so I'm going to check them again (3rd time), but I highly doubt I'll find anything. Perhaps I should reloosen/retighten everything (again) in order (again). Everything was torqued (using a torque wrench even!) to spec.

Does anyone else have this issue? And if so, what did you do to 'fix' it. I'm thinking about just getting an exhaust at this point. I can get a vid if people think it's helpful, but I don't think it will be as it sounds like a high-pitched rattle. Add some gaskets? Is this just an 'it's a subaru, get used to it' thing, and am I just being stupidly neurotic coming from a very quiet mazdaspeed3? I have been known to be like that...