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I am trying to change the sound of the stock muffler without spending $1500.00, so I have cut a spare one open. I will try sealing the holes in the 2 1/2" pipe inside and see how it effects the sound. Here are some pics;
That is all the pics right now, but after I plug those holes I will post more. Does anyone know for sure if that fiberglass packing is to hold the heat off of the rear facia or is it for sound deadening? Thanks
Should be obvious, but if you seal the 2.5" holes on the solid pipe you'll need to keep the exhaust flaps open at all times or else the exhaust will have nowhere to exit.
I will do before and after video and hopefully there will be a difference.
The member was correct, the flaps will have to stay open when the inner holes are blocked.
Maybe drill two more holes at the first up bent in the solid pipe and two holes in the inner pipe for the most flow and with the missing insulation it should be loud yet still operate like stock.
Maybe on the next one you may want to consider an extra cut so you can just lift the cover off and maybe make it smaller and relocate somewhat.
Last edited by C7/Z06 Man; 04-30-2017 at 12:59 AM.
Thanks for this original post. As someone else mentioned, i too am reminded of the C6Z days when I did this mod. A buddy and I went up to the bash this weekend. He just did this to his C6Z and it was perceptibly louder (as well as measured about 10 db louder on my free decibel meter iPhone app) than my C7Z.
Two questions if I may...
(1) when you say the packing is in the front, I assume you mean that wider space between the wall and the end of the can instead of the other side that is much narrower between the wall and the other end of the can - correct?
(2) it looks like you cut the tops of the can open - does it appear that you could get to the packing if you cut from the bottom?
The reason I'm asking is that I did my C6Z on my back in the garage with the car on ramps. It was hard on my hands but I got it done with a cutoff wheel and then got a local muffler guy to weld it back and the I painted them black. I did not have to go through the hassle of removing the exhaust. If I understand the picture correctly, I was thinking on this car that the design was different with the holes but may be worth the effort to cut the cans and at least pull the packing out. I know those are small holes in the straight through pipe but it is just so much quieter than the opened up C6Z.
I realize this will make the flaps closed probably much louder but I don't care about that.
#1 The packing material is in the rear most smaller compartment area which is separated by an interior perforated wall. The larger compartment area contains the "S" shaped pipe w/holes. Sorry for the confusion.
#2 When I cut the mufflers open, I came from the top so the final weld marks would be on top closest to the body so as to hide the scars.
My question; Do you think if I just remove the sound deadening packing material it will attain enough sound increase? I was not only going to remove the material, but also block the holes in the "S" pipe going thru the larger compartment. If I just removed this material and welded things up, I would retain the NPP capabilities.
Originally Posted by Nithros
Thanks for this original post. As someone else mentioned, i too am reminded of the C6Z days when I did this mod. A buddy and I went up to the bash this weekend. He just did this to his C6Z and it was perceptibly louder (as well as measured about 10 db louder on my free decibel meter iPhone app) than my C7Z.
Two questions if I may...
(1) when you say the packing is in the front, I assume you mean that wider space between the wall and the end of the can instead of the other side that is much narrower between the wall and the other end of the can - correct?
(2) it looks like you cut the tops of the can open - does it appear that you could get to the packing if you cut from the bottom?
The reason I'm asking is that I did my C6Z on my back in the garage with the car on ramps. It was hard on my hands but I got it done with a cutoff wheel and then got a local muffler guy to weld it back and the I painted them black. I did not have to go through the hassle of removing the exhaust. If I understand the picture correctly, I was thinking on this car that the design was different with the holes but may be worth the effort to cut the cans and at least pull the packing out. I know those are small holes in the straight through pipe but it is just so much quieter than the opened up C6Z.
I realize this will make the flaps closed probably much louder but I don't care about that.
My thoughts (which are actually just a guess by looking at the pictures) are that removing the packing only would make it a little louder with the flaps open but maybe not that much since only a small part of the exhaust is exiting through those two holes. It also seems it would make the flaps closed a whole lot louder since there would be no packing in there at all.
There are actually 4 approx. 1" holes in the "S" pipe, so who knows how much sound is released into the main chamber of the muffler. I will have to make a decision before sealing these canisters back up.....to plug holes or not to plug holes.
04-28-2017, 10:14 PM
Anatomy of a C7 Z06 exhaust muffler
