Everytime I see a cat-back exhaust for sale, it costs $600-$850 for a new aftermarket rig.
Then there is shipping, then there is install.

Everytime I go to my local muffler shop, they offer rust resistant piping (stainless), mandrel bends, a turbo muffler and a resonator for $250.

I am getting a 2 1/4 catback in the next 2 weeks on my Cobalt.

My wife has a 2 1/4 full exhaust less the header from the same place.
The header was off of Ebay and had excessive welds, uneven ports and a slight warpage of the flange.

That 4:2:1 Tsudo clone header sat for months in its box thanks to it having so many little problems and me having so little time.

I finally drug it outside with the drill and stone attachments and evened up the ports, polished them up and machined the flange down via the concrete (lol), it did not need much rubbing against the smooth concrete and follow up with fine grit sandpaper which I laid out for it to rub across. I polished up the face of the flange when it was done and now I do not see any sunlight peering through when the flange is flat against a flat and even object like a table. Even the gaskets had alignment of the bolt holes and port problems. I once again used the drill to fix.

The end result is, the header fits together perfectly and is match ported and gaskets line up correctly. I should have know a $75 header off of Ebay would do this. At least it is stainless and was fixable.

So, finally... finally will the wife have her 03 Sunfire with its header installed, and finally will I have my first mod. Next is the Speed Concepts header that is a 4:1. Then the Injen CAI. By law I have to wait for 75k to hit the odometer to replace my cat, that is an AZ law, don't ask me why.

 

what 75k to change the cats i just moved from chicago to az and i have like 82k miles on the car will they make me replace them once i change the plates to here

 

I have asked 2 muffler shops to swap my cat and they say it is not legal to do so unless it is damaged or worn and has to be after 75k miles.

 

Aftermarket exhaust,

They start by measureing what the car has, draw up the part on a computer, maybe even do some acoustic modeling, build the aftermarket part, test fit it, modify it if necessary for it to fit, test fit again, then begin production. They also gaurantee that its gona fit.

Custom exhaust

Person starts cutting and bending pipe until it fits. So esentially skips all of the product developement and fitting is done through experience instead of some high paid person in front of a computer. They also typically use cheaper piping.

Whats not to understand.

So, take a hammer to it and put a hole in it. "I need this replaced because its damaged, see the hole there."

 

WTF!!! i have never heard anything like that? i dont even have a gato(cat) a muffler shop removed it

 

yep unfortuanatly its the law. i am a auto tech and by law i cannot replace a cat unless it is diag. as bad. or if i was to gut the cat i can be fined up to $10,000..... seriously. it all gov b/s.>>>heres another crazy one, i have my refrigeration license to do a/c work, but me the professional i have to properly recover every drop of refrigerant before i crack that line but....... a the backyard mechanic can just open that line right up and let all those chemicals in the air. but if i was to do it i would be fined out the a$$

 

I lol'd

 

When I go to Wade's Muffler Shop, he has a mandrel bender that "copies" the existing pipe that it cut off. Kind of like making a spare key.

It is a neat set-up. In fact the 3 other cars I have had exhausts done have always turned out awesome in sound and up and go from his custom exhausts.

If the computers are mapping out how to gain maybe 1 more horsepower, to me it isn't worth the more than double price. My car is just for daily driving and not racing so it doesn't matter.

I am definitely not arguing, I understand your side of it.
I do feel however that people are paying a premium for a name tag.

As for the law, it is dumb and I should pop a hole in it, lol!

 

I just got a custom catback on Tuesday 2.5" Press bent. $387. I LOVE IT! See below:

https://www.cobaltss.net/forums/2-2l-l61-performance-tech-45/%2Anew-mod-today%2A-custom-2-5-catback-pics-56k-beware-172929/

After I had the exhaust installed, I got home and read the really fine print on the reciept. At the end of the LONG paragraph it read "commercial vehicles, custom exhaust, fleet vehicles, & customer installed parts carry no warrenty .................and my next thought was.............oh well.............it's too late now. No Regrets!

 

all the shops I've been to say they won"t take out a cat............but I'm in Indiana

 

highly amused.

 

Did the 2.5" drop a little of your low end and give you some gains on the high end?

I did do a 2.5" exhaust on my 2001 Chevy Prizm LSi and it loved it, unfortunately my ears bled everyday. I had a can muffler, and so I installed two resonators, big ones and it STILL made my ears bleed. I swapped the muffler for a turbo muffler, and it was bearable after that.

So if a 1.8 liter liked a 2.5"...

The problem is, I have no comparison on that car because I didn't go from 2.25" to 2.5"

I am thinking on going 2.25" on the Cobalt 2.2

 

This has a flowmaster 40 series muffler....had to crawl underneeth and look yesterday, all the put on the reciept was "Muffler 42541".....sounds GREAT. Small low end loss under 2000, but after 3000 on up there's a noticeable gain.

 

I have a 2.5 Tsudo catback, stock SS/SC header, stock downpipe. The exhaust mods seemed to help a good but on the midrange to redline but anything below 3k suffered. I still love it.

 

I talked to a guy last night who said that a 2.25" mandrel bent is perfect for most four cylinders cause you don't loose any diameter like press bending.

 

Mandrel bending is the best to my knowledge.

I guess it all depends on what you want, lows and mids or mids and highs.

 

I would have got mandrel bent but the 3 shops i went to didn't have mandrel benders.

 

I got custom piping on mine....high flow cat and a flowtech muffler...works great ..sounds great lol

https://www.cobaltss.net/gallery/sho...mageuser=20224

 

How are the bends over the rear axle, can you take pictures so I can compare it to mine?

 

I will take a pic of my exhaust, it is probably better than most thanks to it being centralized.
It has the Bomber body kit and the exhaust goes all the way down the middle with little to no bends.
Really nice up and go difference thanks to this exhaust.

 

actually most shops dont stock stainless piping. The so-called rust resistant piping is just aluminized piping which will rust after about 1 year. lol