ipse dixit

By louder I mean throatier with a deeper resonance, and not necessarily just decibel louder (although that too, but only a little).

I notice it especially above 5500 rpm, but it is apparent (to me anyway) even down low in the rev range.

Also, this has nothing to do with post "break-in" (whatever that means, whether it's 2000 miles or some other mythical milestone). Cuz, I've been driving my car like the Joker (from Batman fame) since post 991 miles.

Please confirm that this is just my imagination. Thank you.

TRAKCAR

Something might be coming loose or is cracking.

fbroen

A failed changeover valve in the exhaust?

llstuey

I am at 1300 miles and believe the stock exhaust has become slightly louder since around 1k miles - both at throttle as well as more throaty at idle. I wouldn't call it a dramatic change, however.
I had a 911s loaner from new to 3500 miles and that car became significantly louder right around the 2K mark.

991GT3

I am at 19000 km's now, unfortunately I don't think your car will become louder when time goes on.

My car did.

I just 'helped' a little :





Sharkwerks





Stock center muffler





comparison of the stock center muffler (top) compared to the Sharkwerks bypass (bottom)





:-)

Installed last week! I am VERY happy with the sound

SamFromTX

I think you are right. I noticed it as well after the first 1,000 miles or so and it is a subtle but definite change.

ipse dixit

Yeah, it's not a significant much less dramatic change -- either in tone or volume -- but it's there, esp. if you listen for it.

0Q991

Yep. Same for me. After about 1k miles, it got a bit louder and seemed "throatier" sounding.

bronson7

So with the addition of SW, it should really be awesome then !!!

ipse dixit

Wonder if it's metallurgical.

As in repeated heat cycles changing the metal characteristics and bonding of the cats, bypass, whole exhaust system plumbing ...

996FLT6

All I know any car over a track weekend- driving back home it's purring like a kitten like its been uncorked ie been unchoked. Sounds awesome!!! Mike

Jimmy-D

^ I never get a chance to read what you write - sorry

Alan C.

At typical exhaust gas temperatures about the only physical change you will be see is the formation of chrome oxide on the surface of the pipes and mufflers.