My 09 SS came with a Hahn Catback, and with my recent QuickJack purchase was looking around underneath.
Originally, I thought this was a stock downpipe and I've ordered a Hahn downpipe.

After looking at this one, I don't notice a reduced restrictive section so I questioned if this was aftermarket.
It's not a Hahn or a ZZP, so I'm still assuming it's the stock 2.0L downpipe.
But not knowing the 2.0L parts... I wasn't sure.

Is this stock downpipe?

 

It doesn't look like factory one. Might be wrong though. I replaced mine long time ago.

 

looks orig to me from what i have had in the past for ss , 2.0

 

X2 on that.
Actually, who cares unless you are running an adjustable tune ?
As it was said "Rung what you drung".

 

Looks OEM , and a blown gasket at the flange on the left of your first picture

 

hmmm... interesting on the gasket. May be the photo... no leakage when running? Might be...

 

With the high number that passed through your shop... Thanks, to all that "piped" in, appreciate the input!

From my navity, the 2.2 & 2.4 have a narrowed section. The 2.0 appears straight with a different looking flex mesh.

Two canisters... both catalytic?
Exhaust CatBack has resonator & muffler.

 

That's stock. Here's a pic from another thread.

https://www.chevyhhr.net/forums/2-0l...e2/#post744191

Mine's removed, on the garage floor. I'll get a pic of it next time I'm over there. Tomorrow or the next day. It has black on the bottom half of the flange also. I never heard it either.

 

Looked more like a fluid stain from something, visually flang connection looked solid and no noise til exhaust tip. I paid more attention to the flex mesh than coupler flange... but all sounded sealed & tight.

That link was a great Post & Interesting read!