Guys,

As I have mentioned I have been working with www.alteredatmosphere.com to build a cat back exhaust for my SS/SC. Well last week I got a 3 inch stainless steel system installed. It's all mandrel bent and the flanges are all CnC.

The system has a Vibrant muffler and a vibrant race resinator and it's pretty loud. I am going to have a ultra quiet resinator installed once the part comes in.

I don't have any pictures of it in the air becuase I forgot my camera when I picked it up

But I can tell you the welds are look very nice and it lines up nicely along the underside of the car.

So I know the first question in your minds is how much power does it make. Well roughly 10 hp and 10 tq. The dyno's where done in 4th gear.



Full Size Image


You can order the system from them and they can ship it to you. I had it installed by them so I can't tell you how difficult it is to install but it looks pretty simple.

I will post some more pictures once I get them. But the muffler is a round muffler with a 4 inch exit and it seats nicely behind the wind difusser so you can even really is the muffler just the tip.

Bumper View


Resinator


Muffler View


Where the exhaust meets up with the down pipe


Here is the gallery with a few more pictures and more hi res pictures.

Video of the exhaust sound
http://www.cobaltss.org/video/inside-rev.mov
http://www.cobaltss.org/video/outside-idle.mov
http://www.cobaltss.org/video/outside-rev.mov


If you have any question just post them and I will try to answer them.

 

It sounds badass! I loved it at the bash

 

I'm ditching my magnaflow I have on the car right now. It's WAY loud as well. I've even put another resonator on the car. Can't seem to get the damn thing quiet.

I stayed with stock piping and just did the muffler swap and extra resenator.

I have to believe that our cars are doomed for it being loud.

I too went with a round muffler.

It does pull harder too , can't wait for K&N or Injen to compliment the supercharger whine with the exhaust.

 

Well any time you remove restriction your going to have more noise. I am going with an ultra quiet resinator next to try to solve the problem. Mike @ alteredatmosphere already tried it with a 2.5 and said it was a lot more acceptable but didn't have a 3 inch version in stock. It's definetly going to be louder than stock even with the more agressive resinator. The stock resinator is huge!

 

isnt 3" soppuse to be overkill.I went to the website and cant find nothing about ordering it. Could you post a link plz.

 

They don't have a link, you will have to call and ask for one. Mike or Dave should be able to help you out. The exhaust is about 4 days old so I am sure the website isn't setup it yet.

I have asked Mike about a price, hopefully I will hear something tomorrow.

They also have a 2.5 inch one as well but they said the 3 inch made a tad more power (weren't specific). Also I have grander plans for the car so 3 inch made more sense.

They also are working on a down pipe/hi flow cat and maybe a header.

 

Any sound bytes?

 

The GM Perfomance Cobalt SS 272 concept has 3.5" exhaust on it according to the window sticker on the car.....

 

I really don't have a good way to record a sound byte.

 

have him call you and put your cell under your car

 

LMAO. Yeah right now it's pretty darn loud. But that should be fixed with the new resinator.

I love hitting the gas when you go through and underpass.

 

I'll end up calling them but does anyone know if the undercarriage is any different from the Red Line. I am interested in this product.

 

someone needs to figure out a way to put an oval muffler on our car...

 

Thats what I was thinking, I myself am not a fan of the round style mufflers. To me a round muffler is associated with imports.

If GM can fit that huge box under there a oval muffler should fit.

 

will an oval muffler give better performance or is it just going to hide the importish looking muffler?

 

well this may or may not sound stupid but I like to hear what it sounds like before i throw money away . Zinner I trust your opinion and all but I have to hear it. Not real impressed with there web site either. Oh how much$$$ . If I could I am looking for an exhaust that has a real nice low rumble and clean like the exhaust's for the wrx's.

 

I am going to try to record some sound from it I just need to figure out how

 

LOOKS GOOD, how does it sound, new video clip.

 

Video of the exhaust sound
http://www.cobaltss.org/video/inside-rev.mov
http://www.cobaltss.org/video/outside-idle.mov
http://www.cobaltss.org/video/outside-rev.mov


I took some video outside, but it isn't that great, the exhaust is kind of overpowered by all the A/C units in the background. The inside-rev gives the best idea, the two outside clips are drown out by A/C units. I will try to get some more away from the A/C units.

 

Man that sounds so nice.

 

thanks for the clip.. i'll be sure to pass on that exhaust. maybe you could get them to try an oval muffler instead of the fart can? i would be more interested in that

 

an oval muffler keeps your car from having those pops/crackly sounds when you bounce the throttle around like a basketball. because it's not a straight through shot. it gets more of the rasp out of the system, and keeps your car from sounding like it has what i refer to as "mad weed-eater syndrome"

 

Ack, of course you'd make me d/l Quick Time ! Can't wait to hear the clips, still deciding on what to do with my exhaust on my LS (and by the sounds of it the magnaflow I had planned might be too loud). I don't mind it making a little more noise but don't wanna sound like an overpowered lawnmower coming down the street.

Permafried-

 

Okay now, How much is it!

 

599. ordered mine today. cant wait.