2009 C6 LS3 is too Quiet
Thread Starter
Heel & Toe
Joined: Feb 2009
Posts: 23
Likes: 0
From: St. Charles Louisana
Regarding the NPP's. I purchased a complete 2007 ZO6 exhaust system which included the ZO6 npp mufflers. Prior to that I had the Corsa Sports with the oem x-pipe. They are louder than the ZO6's with the flaps open. However, I do enjoy the deeper rumble from the ZO6 h-pipe.
So, researching I found that alot of forum members that have the npp's have done the muffler sound upgrade. You cut a 7"x7" panel out of each muffler remove the sound deading material then wrap the preforated exhaust tube and weld it in or use muffler clamps to hold the sleeve in. Weld it back up sand it down then spray it with heat resistant black paint and reinstall. Results a solid 30-40% sound increase when you have the flap open. Cost averages out to ~ $250. Benefit: it's quite when you need it and nice and loud when needed. This is my next mod after I get the car tuned for the ZO6 exhaust system. Thanks, Dewman
So, researching I found that alot of forum members that have the npp's have done the muffler sound upgrade. You cut a 7"x7" panel out of each muffler remove the sound deading material then wrap the preforated exhaust tube and weld it in or use muffler clamps to hold the sleeve in. Weld it back up sand it down then spray it with heat resistant black paint and reinstall. Results a solid 30-40% sound increase when you have the flap open. Cost averages out to ~ $250. Benefit: it's quite when you need it and nice and loud when needed. This is my next mod after I get the car tuned for the ZO6 exhaust system. Thanks, Dewman
My wife & I really do not go on long trips in our Toy 
.
Instructor
Joined: Feb 2009
Posts: 144
Likes: 0
From: Allen TX
I'm with the OP....
would like some ooomph in the sound of my new '08 LS3....
the NPP's sound like what I want, because I like the idea of being able to control the sound .....quiet/not so quiet.....
sorry for the noob question, but is NPP a brand or do all of the manufacturers...Corsa, Borla, etc. have comparable???? My car is 4 months old and would like a nice system without a huge investment, due to my major investment 4 months ago....
I like the interior switch mods available on the forum that you control from the dash, thru the fuse box....
would like some ooomph in the sound of my new '08 LS3....
the NPP's sound like what I want, because I like the idea of being able to control the sound .....quiet/not so quiet.....
sorry for the noob question, but is NPP a brand or do all of the manufacturers...Corsa, Borla, etc. have comparable???? My car is 4 months old and would like a nice system without a huge investment, due to my major investment 4 months ago....
I like the interior switch mods available on the forum that you control from the dash, thru the fuse box....
Melting Slicks
Joined: Dec 2006
Posts: 2,887
Likes: 2
From: Exhaust Commander Wireless Bi-Mode Exhaust Controllers, Innovative and advanced technology! --- Check out our website @ www.sunsetorangecreations.com
St. Jude Donor '13
I think the bi-mode mufflers are great. They are the best of both worlds.
You can have it Loud when you want it and also whisper Quiet when you want.
With my Exhaust Commander All-in-1 bi-mode exhaust retrofit kit its easy to add to any car.
I have many options available on my bi-mode exhaust retrofit kit. You can have user selectable rpm opening, you can open and close the exhaust from your dash DIC reset button, and you get a kit that remembers its last setting so that the position you turn the car off in is the position it will return to when the car starts.
Here is the CF thread that tells all about the Exhaust Commander NPP retrofit kit. ---> Exhaust Commander All-in-1 NPP retrofit kit.
I have helped many people get their bi-mode exhaust up an running so feel free to contact me anytime for any information.
Ben
You can have it Loud when you want it and also whisper Quiet when you want.
With my Exhaust Commander All-in-1 bi-mode exhaust retrofit kit its easy to add to any car.
I have many options available on my bi-mode exhaust retrofit kit. You can have user selectable rpm opening, you can open and close the exhaust from your dash DIC reset button, and you get a kit that remembers its last setting so that the position you turn the car off in is the position it will return to when the car starts.
Here is the CF thread that tells all about the Exhaust Commander NPP retrofit kit. ---> Exhaust Commander All-in-1 NPP retrofit kit.
I have helped many people get their bi-mode exhaust up an running so feel free to contact me anytime for any information.
Ben
Melting Slicks
Joined: Dec 2006
Posts: 2,887
Likes: 2
From: Exhaust Commander Wireless Bi-Mode Exhaust Controllers, Innovative and advanced technology! --- Check out our website @ www.sunsetorangecreations.com
St. Jude Donor '13
If you use Z06 bi-mode mufflers you will need to do some fabrication to mate the 3 inch z06 piping to the 2.5 inch piping on a C6. the Z06 bi-mode mufflers are nt a direct bolt in on a C6.
If you need more info let me know.
Ben
Heel & Toe
Joined: May 2009
Posts: 23
Likes: 0
From: CO
Just did the muffler mod this weekend. I created a photo album to show the steps in the process.
I removed Flowmasters (too much drone on the highway after I installed headers and catted x-pipe) and replaced them with the modified Z06 mufflers last night. I have to say the muffler mod doesn't sound SWEET like the Flowmasters but the bi-mode feature is really cool and the car is quiet on the highway now.
I HIGHLY SUGGEST listening to various exhaust options IN PERSON before you buy. Listening to different mufflers on the internet is helpful but doesn't truely give someone a complete understanding of what it's really like in person.
I removed Flowmasters (too much drone on the highway after I installed headers and catted x-pipe) and replaced them with the modified Z06 mufflers last night. I have to say the muffler mod doesn't sound SWEET like the Flowmasters but the bi-mode feature is really cool and the car is quiet on the highway now.
I HIGHLY SUGGEST listening to various exhaust options IN PERSON before you buy. Listening to different mufflers on the internet is helpful but doesn't truely give someone a complete understanding of what it's really like in person.
Racer
Joined: Jun 2006
Posts: 479
Likes: 0
From: New Port Richey Florida
I find my 08 with bullets to be a little too quiet for me. I was really surprised after installing them considering the way bullets are talked about on this site. Different demographics obviously, but still!
BTW, not saying my car doesn't sound amazing! I just wouldn't use words like "obnoxious" or "drone" when describing it.
BTW, not saying my car doesn't sound amazing! I just wouldn't use words like "obnoxious" or "drone" when describing it.
Former Vendor
Joined: Sep 2008
Posts: 2,695
Likes: 0
From: Brightwaters NY
St. Jude Donor '09
here is the process on a C6 using headers and npp mufflers, check out the videos and you will hear what a great system this is
Here is the complete process
Here is the complete process
NakidParts NPP in a box, a set of NPP mufflers will give you an incredibly easy way to have just the sound you want, when you want, if you have a pre-2008 C6. In my case, throw in a set of LG headers, and you have rolling thunder at the flick of a switch. The combo of the headers and the NPP in Wild gives you AMAZING sound and “HEY, LOOK AT ME!!!” volume…the tonality and sound is that of a NASCAR stock car at WOT outside the car, yet quieter and less drone inside the car than the GHL exhaust I was so fond of. The install is very straight forward, easier with a lift, but as Ed has shown with his car, you can do it on jack stands. Here are some pics and descriptions of the step by step process; you will receive complete illustrated instructions with your purchase.
NPP Mufflers waiting for Install
Factory Exhaust Removed
Drilling a ¼” hole in the rear well
Run the Vacuum Tube though the hole
Run the Vacuum tubes through existing frame locations
After dropping the rear sway bar, snake the NPP mufflers up and over
Attach the pipes to the mufflers
Connect the vacuum hoses to the NPP mufflers
Make sure your muffler pipes are straight and level
Muffler hardware done and vacuum tubing run
Connect power cable to the Seat Heater Fuse
And of course, a quick run with Ed's Polishing kit
Nakidparts = NPP in a box
That's all there is to it.....All that's left is to go out there and have a blast with your new found customized sound.
Here's a link to a video of the sound
Play Video
Ed, once again, THANK YOU!!!!
NPP Mufflers waiting for Install
Factory Exhaust Removed
Drilling a ¼” hole in the rear well
Run the Vacuum Tube though the hole
Run the Vacuum tubes through existing frame locations
After dropping the rear sway bar, snake the NPP mufflers up and over
Attach the pipes to the mufflers
Connect the vacuum hoses to the NPP mufflers
Make sure your muffler pipes are straight and level
Muffler hardware done and vacuum tubing run
Connect power cable to the Seat Heater Fuse
And of course, a quick run with Ed's Polishing kit
Nakidparts = NPP in a box
That's all there is to it.....All that's left is to go out there and have a blast with your new found customized sound.
Here's a link to a video of the sound
Play Video
Ed, once again, THANK YOU!!!!
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Melting Slicks
Joined: Dec 2006
Posts: 2,887
Likes: 2
From: Exhaust Commander Wireless Bi-Mode Exhaust Controllers, Innovative and advanced technology! --- Check out our website @ www.sunsetorangecreations.com
St. Jude Donor '13
Here is the video...
On my 2005 C6 with retrofitted bi-mode exhaust !
Ben
Racer
Joined: Jun 2008
Posts: 350
Likes: 1
From: Fla
Dyno results
I had Jeremy F. tune my car yesterday. I had a full 07 ZO6 exhaust installed the week before.
Went from 405/395 to 415.62 /404.77 Run conditions were 92.16* F, 29.96 in-Hg,SAE:1.02 on a in ground Dyno jet.
One very interesting item was with the flap closed on the ZO6 Npp mufflers. closed: = 402.43/395.30 opened: = 413.13 / 403.60
What's nice when driving the air temp drops and you add more hp. 1hp for each 10* drop. Driving home last night it was around 78* and you feel the extra hp. Kudo's to Jeremy.
Also I have LEAA Customs NPP in a box and I love that remote.
Went from 405/395 to 415.62 /404.77 Run conditions were 92.16* F, 29.96 in-Hg,SAE:1.02 on a in ground Dyno jet.
One very interesting item was with the flap closed on the ZO6 Npp mufflers. closed: = 402.43/395.30 opened: = 413.13 / 403.60
What's nice when driving the air temp drops and you add more hp. 1hp for each 10* drop. Driving home last night it was around 78* and you feel the extra hp. Kudo's to Jeremy.
Also I have LEAA Customs NPP in a box and I love that remote.
Last edited by Velocity2008; Jun 7, 2009 at 08:08 AM.
