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Old 02-14-2017, 10:17 AM
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Privateeye007
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Default NPP Exhaust

I have a 16Z with NPP and I have removed the fuse that allegedly keeps the baffles open, but to be honest it still sounds like a "weenie". I also went into "exhaust settings" and set it on Track. Is there anything else I can do to get more sound (I know it's in there somewhere) without adding hardware? If nothing else can be done, what is the best bang for the buck? Thanks
Old 02-14-2017, 11:50 AM
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davepl
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People talk about pulling fuses but it's not as loud as my C6Z was at idle even so; however it's lot louder under load!

I put in an X-pipe that removes the rear cats. It's a balance. I didn't want drone in Tour but I wanted it louder in Sport and Track, and that's what I got. Still quiet in Tour.

Even so, it's not rocking loud at idle, and doubt it ever will be.
Old 02-14-2017, 03:46 PM
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lakemg
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As Dave mentioned, the next best bang for your buck will be an x-pipe that eliminates the second set of cats. If that doesn't do it, the next step is headers with high flow cats. if that doesn't do it, it's headers with no cats.

From all the exhaust experimenting (self educating) that I did with my 2009 Pontiac G8 GT, I went straight to long tube headers + high flow catted midpipe + NPP mufflers. Sounds amazing (to me). It is loud, but not obnoxiously loud unless my foot is in it and the NPP valves are set to track mode. Love it!!!

Last edited by lakemg; 02-14-2017 at 03:48 PM.
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Old 02-14-2017, 08:42 PM
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robert miller
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Originally Posted by Privateeye007
I have a 16Z with NPP and I have removed the fuse that allegedly keeps the baffles open, but to be honest it still sounds like a "weenie". I also went into "exhaust settings" and set it on Track. Is there anything else I can do to get more sound (I know it's in there somewhere) without adding hardware? If nothing else can be done, what is the best bang for the buck? Thanks
Cut the mufflers out and replace with just pipe. It really is not that much louder in the car. A few DIY post in here on it.

I also have NPP I have put LG LT headers so that is pulling the back 2 cats from the car, then 3 inch mid pipe, with the Borla ATKA cat back on it. For a sound to money spend it was a waste of money and time. Really not much over the stock sound until you get in WOT in the car. Robert

Last edited by robert miller; 02-14-2017 at 08:45 PM.
Old 02-15-2017, 07:25 AM
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TPAJETSKI
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Originally Posted by robert miller
Cut the mufflers out and replace with just pipe. It really is not that much louder in the car. A few DIY post in here on it.

I also have NPP I have put LG LT headers so that is pulling the back 2 cats from the car, then 3 inch mid pipe, with the Borla ATKA cat back on it. For a sound to money spend it was a waste of money and time. Really not much over the stock sound until you get in WOT in the car. Robert
I am assuming you guys cutting mufflers have M7s? I would think anytime the car switches to V4 the sound is terrible.
Old 02-15-2017, 08:40 AM
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Rod2013C6
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M7 cars only go to 4cyl mode if you put it in eco mode...muffler delete is the way to go for what you are looking for in exhaust sound
Old 02-15-2017, 07:45 PM
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robert miller
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Originally Posted by TPAJETSKI
I am assuming you guys cutting mufflers have M7s? I would think anytime the car switches to V4 the sound is terrible.
No those guys cut the muffler off back up close to the axle just after that elec hook up for the exhaust pipe. Then just welded in a pipe without any mufflers at all. Then welded on a set of tips out the end of the car to make it look like it does have muffler's under the car.

But I did see in here ONE guy did cut a set of stock mufflers open and pulled out all of the stuff on the inside of it. I never did hear a sound clip of this set up. But the cut out and deleted the mufflers totally yes he did make a sound clip of it. Robert
Old 02-23-2017, 09:50 AM
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keithafd
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I have 2016 with npp texas speed headers no cats it sounds Awesome!! in sport and track mode. tour mode nice and quiet no drone absolutely perfect!
Old 02-23-2017, 12:59 PM
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Originally Posted by TPAJETSKI
I am assuming you guys cutting mufflers have M7s? I would think anytime the car switches to V4 the sound is terrible.
I have a auto A6 trans in the car. If I had it to do over with the car I would have just cut the mufflers out from under the car and did pipe only in their place. Robert
Old 02-23-2017, 06:46 PM
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Privateeye007
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Default Warranty

Let me ask, do any of these "cutting" proposals in any way cause problems with a car still under warranty? It sounds like the cheapest way, cutting the mufflers out and doing pipes, but how do they sound with everything else stock? And I do question when the dang thing slips back into that 4 cyl. mode.....which I understand happens in all modes except track mode (correct me if I am wrong).

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