ayelien

Engine experts!
2001 S, 27,000 miles,
I have a metalic sounding rattle that occurs from 4100 RPM up. Below that nothing.
It is very predictable right at about 4100.
I do not seem to get the rattle when I run the RPM's up in neutral only in gear.
It seems to be a rattle not a vibration in the drivetrain and is comming more from the front to mid section of the car but thats a guess.
I am running an Invicta cat back dual exhaust and at first I though it was just an exhaust rattle but upon securing the sytem pretty good and finding I don't get it when I'm in neutral it now seems like its a drive train issue.
Has anyone else experienced a similar issue?
What might be the most probable causes?

03_BB_S2K

perhaps a heat shield on the primary catalytic converter or perhaps it might be the heat shield on the exhaust manifold

APOSTLE SBG

I have something similar but it's just between 4,500-5,000. Doesn't seem to do it all the time though. I also have an Invidia.

ayelien

I'll check out the heat shields, it kind of sounds metallic like rattling sheet metal rather than a loose bolt let say but who knows.
It's extremely controlled though, starts almost exaclty @ 4100 all the time every time and goes up. (Failed to mention I was supercharged so homey don't like drivng uder 4100 RPM to much.)
I'm currious on your Invidia, what has been your experience? Did you have any rattles before you put the system on? How did you mount and secure your system? The stock system has a stand pipe coming off the side of the main pipe. I would like to know what the function of that pipe is and if there is any implications for a system like the Invida which eliminates it?