Hi All, As you can see from my sig, I have Magnaflow exhaust system on my car. Here is what I got: http://www.hopupracing.com/maducatbaexs.html I have it installed, and the sound is great. Very deep bass/rubmle at the lower RPM's. Dosent sound like and 8, but it sounds pretty close and you can definitely hear the american muscle car heritage in it. Now for my questions, and I hope some of you can help. I took it to my mechanic and he put it in. He had to fabricate a cutom hanger for the driver side muffler to make it fit the hole on the left side of my GT bumper. I was under the car after the install and it is very tight. However, I get two types of sounds one in every 4 stop lights when the car is idleing, as follows: 1. rattling at the rear of the car, sometimes very noisy 2. popping sound, though this seems rare I have read that there is a break in period for mufflers and the more I drive, the less and less I hear the popping sound...i think. But the rattling is very annoying and I can't tell what it is. Getting under the car and looking at the pipes and they are very secure and firm. Any ideas on this one? I want to resolve this before I do any other work on it. Thanks for your help.