JD, J--eater & others
Wish to thank you for the help & suggestions you've offered.
I now have a BC that has a pair of keys and each key operates all 4 of the 08Ls's locks.
Replacement door speakers should arrive via fedex today
Boss ch6530. I hope they sound as good as oem. Remembering this is a car and not a concert hall.
The reason for the post is Headers.
While the 18yr old kid in me would like to,rat around with +400hp,
the hassel with revenuers is not my idea of fun.
Yet a bit more effeciency wouldn't hurt.

So, tell me about stock Cobalts w 4-into-1 tuned exhaust with reasonable exhasust. Thinking a new Magnaflow Cat would be in order about now (113k miles)
Any thoughts! Benifits, disadvantages?....

 

I high quality header with a good catback sounds good.

 

What 's a good 4-2-1 and at size exhaust 2-1/2. More or less?
Anything better than stock mufler for quiet without power loss, does it even exist?
3" x14" resonator?

Just dont want the chain saw noise.

 

Very few lsj's sound good.

Hopefully Bluelightening see's this. He had a great sounding exhaust on his. Most I've heard drone like a mother.

 

My LSJ had zero drone, but that was due to my rare Corsa Touring catback.

I ran a ported gmpp extrude honed manifold which gm tested to be good to 350hp.

I highly recommend it.

 

it looks like it's an 08 LS if I deciphered that correctly

 

Ok just to point out, this is a stock 08 LS wit 113k. While a complete blower package would be nice.
For this old engine, just trying to let it breath a little better, and a good set of 4-2-1 will help suck the exhaust out.
Yet as new to the eotechs as i am, i dont know good from junk yet. Also needing to annualy have a probe up the wazoo and all IM monitor ready, i defantly not looking to cause any known errors with the ecu attempting to control the engine and throwing cel because of some fubar

 

does your have secondary air injection? that could preclude you from getting a header

 

JE , i dont know.
It was first delivered in 08 and live in San Antonio for the first few years.
And i dont know enough about any one year to say.
I would need to go out and look. Would this be like air injection on exast mfld similar to 69 427?
I believe the system is shown by MP81's post about " two cats better than one" over at yourcobalt shows the back. Ill go out and look at my manfld tomsee if there is an air port/ line to it

 

For a catback 2.5" is all you need. I ran a 2.5" catback with ZZP's resonator and a walker quietflow muffler. Sounded mint. ZZP's resonator will be your saving grace. Don't go with a small crappy one like a magnaflow. Been there, tried that.

 

I need to get the specs on that resonator.
1: 2.5 INCH STAINLESS 2.2L DOWNPIPE
2: 2.5 INCH STAINLESS COBALT CATBACK EXHAUST
???
You beat me to it

 

Ecotec Parts ZZP Resonator Section for Catback - Exhaust