So this is funny. My neighbor walked over the other day to check out the new stang. He asked me what exhaust i put on it since i bought it. i told him i hadn't changed it. He said that the car was much louder when it starts than it was when i bought it home. After i started paying attention to it, the exhaust is much louder now than when i first got it. Car has 500 miles on it now. First 300 miles the car stank horribly when i stopped after driving, horrible burning smell from the exhaust. My 5-year-old daughter said "you car smells like poo poo daddy" the first few times i drove home, no more smell now though.

He will really hate me when i get around to adding that roush extreme exhaust system.

 

Its just the break in stuff wearing off. All my cars did it when new. Smells like burning rubber right? I know that with all exhausts it takes a few hundred miles for them to break in and settle. So I would say thats normal.

 

I would not know as the first mod on the first day or two is to lower the 4x4 and rip off the exhaust for something deeper/louder.

 

Exhaust seems to get a little louder with time in all of them. No packing in the mufflers that I know of so only thing I can come up with is that maybe it has something to do with the cats breaking in. Then again maybe its all in our heads.