hey everybody I got my 2007 cobalt ss s/c this past friday and its going back to the dealership for a stage 1 & 2 this thursday. as soon as i get it out i want to go to an exhaust shop over by my place. ive heard that just replacing the stock muffler is just as good as getting an after market exhaust. im going to hook up the dynomax ultra flow muffler to it. its flows 1300 cfm, so its a high flowing muffler and should sound good. well not sure how true that is and i figured id get some ideas from you guys. also i do plan on getting headers and a nice down pipe but in the future.

 

That is not true. You need to do a cat back and if you are wanting to stick to GM only go with the gmpp exhaust. Otherwise I prefer magnaflow.

 

a muffler just alone will do nothing. you would need to replace all the piping hence "Cat-Back" to notice any performance gains. and who ever told you a muffler is all you need... you need to like not talk to him anymore about cars...

 

well i believed him because when i had my eclipse gt v6, the piping from the cat back was just as good as a catback unless you stepped up into a bigger size. Well i was just checking, do you guys know what parts on the warranty will be voided if i have a custom one made and not buy the GM exhaust??

 

Aftermarket kits are stainless and with mandrel bends...

your local muffler shop doesnt have either..

and aftermarket catback exhaust CAN'T void your warranty by law..

 

yea i have a aftermarket muffler ....on right now...im getting my megan drift spec catback system put on tomorrow cant wait im so excited

 

The stock muffler is restrictive, but by replacing the stock muffler your flow will be only as good as a 2.25" cat-back. Now change the muffler and replace the 2.25" section of the exhaust with a 2.5" mandrel bend section and you will be good.

 

Replacing the muffler will not give you the same effect. I have a custom Magnaflow set-up and it sounds great. Going to an exhaust shop is better than buying an exhaust in a box because they will make your exhaust one continuous pipe up to the down pipe as opposed to breaking up the sections with a bolt-on kit.

 

The only thing about going to an exhaust shop is if they do not have a mandrel bender then your pipe will be smaller at the bend crush or not. So if you go with a 2.5" pipe at the bend you will be almost back to 2.25" pipe. I was going to go this route at first until we made the bend and took a measurements and backed out. I just popped on the muffler and waited until I could find a shop that had a mandrel bender and did it that way. The magnaflow muffler sounds great and even before I added the 2.5" mandrel section I could fill a slight increase in power but not as much as when I added the new mandrel section of pipe.

 

ok i got it. cause i think the muffler shop i went to before has a mandrel bender. i think ill go with a 2.5" pipe then. is this the best size pipe or what?? also anybody have any clips of custom exhausts??

 

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