NPP install on A6
06-23-2015, 12:43 PM
#1
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NPP install on A6
I'm picking up a used bi mode exhaust off a manual C6 today and as I read more and more, I'm seeing post about it being difficult to install on automatics. It's getting installed on an 08 auto and does anyone have any experience with this. I know the piping is 3" to my 2.5". I plan on running it open for now until I get a controller for it. Any input is welcome. Thanks
06-23-2015, 04:13 PM
#2
Team Owner
Since you're new here, let's please get the terminology straight, if just for the sake of your future discussions here. 
NPP is an RPO code for the "dual mode" muffler system on a C6, it is 2 1/2" pipe all the way from engine to mufflers.
"Dual Mode" is the only descriptor used for the dual mode muffler system on a C6 Z06, it is 3" pipe all the way from engine "up to" mufflers where it reduces to 2 1/2" going into the dual mode mufflers. The Z06 dual mode mufflers ARE NOT the same as NPP mufflers, they sound very different.
Now, your thread title says "NPP install on A6", but your narrative says "bi mode exhaust off a manual C6" and "I know the piping is 3" to my 2.5". Your terminology is mixed and confusing so we don't actually know what you are buying/installing.
IF you are actually getting a Z06 3" exhaust, there will be interference issues when getting it installed next to the A6, but others here have reported that appropriate application of hammer blows to dent the 3" pipe in the right place(s) will allow it to work, it just won't be smooth and factory looking, but who sees it anyway right?
IF you are not getting a Z06 3" exhaust, but actually any other '08 non-Z06 C6 2 1/2" exhaust, then you will not have an issue, UNLESS it is an '09 or later C6 2 1/2" setup. IF that is the case, you will also need the '09 and later x-pipe to go with the new setup because they changed the angle of the passenger side pipe in '09 and later and those will not bolt directly up to the '08 x-pipe.
NPP is an RPO code for the "dual mode" muffler system on a C6, it is 2 1/2" pipe all the way from engine to mufflers.
"Dual Mode" is the only descriptor used for the dual mode muffler system on a C6 Z06, it is 3" pipe all the way from engine "up to" mufflers where it reduces to 2 1/2" going into the dual mode mufflers. The Z06 dual mode mufflers ARE NOT the same as NPP mufflers, they sound very different.
Now, your thread title says "NPP install on A6", but your narrative says "bi mode exhaust off a manual C6" and "I know the piping is 3" to my 2.5". Your terminology is mixed and confusing so we don't actually know what you are buying/installing.
IF you are actually getting a Z06 3" exhaust, there will be interference issues when getting it installed next to the A6, but others here have reported that appropriate application of hammer blows to dent the 3" pipe in the right place(s) will allow it to work, it just won't be smooth and factory looking, but who sees it anyway right?
IF you are not getting a Z06 3" exhaust, but actually any other '08 non-Z06 C6 2 1/2" exhaust, then you will not have an issue, UNLESS it is an '09 or later C6 2 1/2" setup. IF that is the case, you will also need the '09 and later x-pipe to go with the new setup because they changed the angle of the passenger side pipe in '09 and later and those will not bolt directly up to the '08 x-pipe.
06-23-2015, 08:21 PM
#3
Right on RickT. Perfect explanation. Only thing i would add is that a competent custom muffler shop can install anything. 3" tubing or '09 or newer 2 1/2". I just sold my bimodes and the shop ended up cutting off the stock 2 1/2" pipe and welded them to the back of the bi modes. Anything is possible. But like u said for bolt ons in your garage u need to get all the right parts.
06-23-2015, 09:10 PM
#4
Race Director
sunset orange creations for the controller. worth every penny.
also get a vacuum canister and install right before the valves. it will keep the flaps closed under light load say a long slight grade when the vacuum runs low, otherwise the exhaust flaps open and it drones.. the vacuum canister was $10 or so.
also get a vacuum canister and install right before the valves. it will keep the flaps closed under light load say a long slight grade when the vacuum runs low, otherwise the exhaust flaps open and it drones.. the vacuum canister was $10 or so.
06-23-2015, 10:41 PM
#5
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Since you're new here, let's please get the terminology straight, if just for the sake of your future discussions here.
NPP is an RPO code for the "dual mode" muffler system on a C6, it is 2 1/2" pipe all the way from engine to mufflers.
"Dual Mode" is the only descriptor used for the dual mode muffler system on a C6 Z06, it is 3" pipe all the way from engine "up to" mufflers where it reduces to 2 1/2" going into the dual mode mufflers. The Z06 dual mode mufflers ARE NOT the same as NPP mufflers, they sound very different.
Now, your thread title says "NPP install on A6", but your narrative says "bi mode exhaust off a manual C6" and "I know the piping is 3" to my 2.5". Your terminology is mixed and confusing so we don't actually know what you are buying/installing.
IF you are actually getting a Z06 3" exhaust, there will be interference issues when getting it installed next to the A6, but others here have reported that appropriate application of hammer blows to dent the 3" pipe in the right place(s) will allow it to work, it just won't be smooth and factory looking, but who sees it anyway right?
IF you are not getting a Z06 3" exhaust, but actually any other '08 non-Z06 C6 2 1/2" exhaust, then you will not have an issue, UNLESS it is an '09 or later C6 2 1/2" setup. IF that is the case, you will also need the '09 and later x-pipe to go with the new setup because they changed the angle of the passenger side pipe in '09 and later and those will not bolt directly up to the '08 x-pipe.
NPP is an RPO code for the "dual mode" muffler system on a C6, it is 2 1/2" pipe all the way from engine to mufflers.
"Dual Mode" is the only descriptor used for the dual mode muffler system on a C6 Z06, it is 3" pipe all the way from engine "up to" mufflers where it reduces to 2 1/2" going into the dual mode mufflers. The Z06 dual mode mufflers ARE NOT the same as NPP mufflers, they sound very different.
Now, your thread title says "NPP install on A6", but your narrative says "bi mode exhaust off a manual C6" and "I know the piping is 3" to my 2.5". Your terminology is mixed and confusing so we don't actually know what you are buying/installing.
IF you are actually getting a Z06 3" exhaust, there will be interference issues when getting it installed next to the A6, but others here have reported that appropriate application of hammer blows to dent the 3" pipe in the right place(s) will allow it to work, it just won't be smooth and factory looking, but who sees it anyway right?
IF you are not getting a Z06 3" exhaust, but actually any other '08 non-Z06 C6 2 1/2" exhaust, then you will not have an issue, UNLESS it is an '09 or later C6 2 1/2" setup. IF that is the case, you will also need the '09 and later x-pipe to go with the new setup because they changed the angle of the passenger side pipe in '09 and later and those will not bolt directly up to the '08 x-pipe.
Thanks for the info.
I always wondered why I kept seeing NPP and Bi mode but kept seeing the same exhaust operation (at least I thought I did)
06-23-2015, 10:45 PM
#6
Racer
I'll second the Sunset Orange Creations for the controller. I installed the "elite" commander and that allows me to control the opening and closing by engine rpm in addition to ether open or close setting.
06-24-2015, 06:49 AM
#7
sunset orange creations for the controller. worth every penny.
also get a vacuum canister and install right before the valves. it will keep the flaps closed under light load say a long slight grade when the vacuum runs low, otherwise the exhaust flaps open and it drones.. the vacuum canister was $10 or so.
also get a vacuum canister and install right before the valves. it will keep the flaps closed under light load say a long slight grade when the vacuum runs low, otherwise the exhaust flaps open and it drones.. the vacuum canister was $10 or so.
06-24-2015, 07:38 AM
#8
Instructor
I agree with what the others have said. I had a full Z06 conversion done earlier this Spring on my A6. I had it done at a shop but I watched the whole process.
I think it will be a little tricky to wrestle the new mufflers over the rear axle in your driveway... it looked like they had a hard time with it on the lift. With a little heat and a little persuasion you can shape the pipes around the A6 and give yourself enough clearance to avoid heat issues.
I wouldn't plan on running them open all the time. They do drone when open especially when going up a grade under load. Invest in a controller. The newer models no longer require you to tap a vacuum line and they can be installed behind the trim panel in the trunk so they don't take up valuable trunk space.
I think it will be a little tricky to wrestle the new mufflers over the rear axle in your driveway... it looked like they had a hard time with it on the lift. With a little heat and a little persuasion you can shape the pipes around the A6 and give yourself enough clearance to avoid heat issues.
I wouldn't plan on running them open all the time. They do drone when open especially when going up a grade under load. Invest in a controller. The newer models no longer require you to tap a vacuum line and they can be installed behind the trim panel in the trunk so they don't take up valuable trunk space.
06-24-2015, 09:02 AM
#9
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I won't be installing these myself; will have a shop install for me. In my mind, I plan on getting the pipes cut closer to the mufflers and having them wielded on. Would like to run them mostly open but only can handle drone for so long.
06-24-2015, 09:24 AM
#10
Instructor
You'll get a great sound when you are done... especially if you have the paddle shifters. Second gear provides lots of great V8 noises that the stock exhaust hides from you.
I recently came back from a run through the mountains of Kentucky and NC. I can tell you I was glad to have the controller. Open is fun around town but going up a long hill at 60 to 70 MPH will rattle your brain after about 15 minutes.
06-24-2015, 09:50 AM
#11
Le Mans Master
I installed mine years ago with no issues at all. I have a lift and believe that the "fitment" issue is when you don't have the car high enough off the ground when trying to install the system. i did not even touch the sway bar or links, FWIW. You are not going to do it so you should have no worries.