NPP fuse pull trick/result
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
First day drive report.
Pulled fuse 41 as promised, and drove up the coast about a 150 miles.
Now the car maintains the same growl as when it first fires up from idle trough the 1700 rpm tip in point where it use to be reopened up.
It now sounds like I wanted it to when I turned the "sound Management" off in the first place.
My original expectations of the NPP exhaust option was to control (turn on and off) the sounds & tones of what previous generation C6 aftermarket exhaust system sounded like at a touch of a dial.
With the fuse removed it's more like a sweet aftermarket exhaust system tone all the time.
On the open highway I even experimented with the sound of the car in "Eco" mode. In 7th gear cruising at 70 mph the tachometer was right at 1500 RPM and running in V4 "Eco" mode and didn't sound that bad at all.
I think the reason it didn't negatively effect the sound quality as much as some here had feared is because, just as soon as you gas it just a bit more still cruising in 7th gear to around 1600-1700 or 72 mph it kicks back into V8 mode and the beautiful rumble come right back almost as it did before the fuse pull.
The only time I noticed the exhaust tone in "Eco" mode sound a little funky/raspy was at idle when I got out and walked behind the car.
Not horrendously bad like a riced out Honda with a fart can muffler bad.
I don't normally use "Eco" mode I just tried it today to report back here with my findings.
My Stingray sounds like a real sports car now.
No CEL's so far, and I'm very pleased with the results!
Thanks again xp800, I think from here forward this great zero cost mod. should be named after you the "the xp800 exhaust mod."
Cheers.
Pulled fuse 41 as promised, and drove up the coast about a 150 miles.
Now the car maintains the same growl as when it first fires up from idle trough the 1700 rpm tip in point where it use to be reopened up.
It now sounds like I wanted it to when I turned the "sound Management" off in the first place.
My original expectations of the NPP exhaust option was to control (turn on and off) the sounds & tones of what previous generation C6 aftermarket exhaust system sounded like at a touch of a dial.
With the fuse removed it's more like a sweet aftermarket exhaust system tone all the time.
On the open highway I even experimented with the sound of the car in "Eco" mode. In 7th gear cruising at 70 mph the tachometer was right at 1500 RPM and running in V4 "Eco" mode and didn't sound that bad at all.
I think the reason it didn't negatively effect the sound quality as much as some here had feared is because, just as soon as you gas it just a bit more still cruising in 7th gear to around 1600-1700 or 72 mph it kicks back into V8 mode and the beautiful rumble come right back almost as it did before the fuse pull.
The only time I noticed the exhaust tone in "Eco" mode sound a little funky/raspy was at idle when I got out and walked behind the car.
Not horrendously bad like a riced out Honda with a fart can muffler bad.
I don't normally use "Eco" mode I just tried it today to report back here with my findings.
My Stingray sounds like a real sports car now.
No CEL's so far, and I'm very pleased with the results!
Thanks again xp800, I think from here forward this great zero cost mod. should be named after you the "the xp800 exhaust mod."
Cheers.
Well, I guess it's time to tinker now that she's running again. The first hurdle will be what to use in the shallowness of the fuse box cover, but I have a few ideas. Second will be how to waterproof the box, but that also shouldn't be too hard.
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
Tech Contributor
Joined: Aug 1999
Posts: 16,376
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From: Should this thoughtful, valuable contribution meet with no acknowledgement or 'thanks' this post----
Very good - more points of data are a great thing!
Well, I guess it's time to tinker now that she's running again. The first hurdle will be what to use in the shallowness of the fuse box cover, but I have a few ideas. Second will be how to waterproof the box, but that also shouldn't be too hard.
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
Well, I guess it's time to tinker now that she's running again. The first hurdle will be what to use in the shallowness of the fuse box cover, but I have a few ideas. Second will be how to waterproof the box, but that also shouldn't be too hard.
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
Bring it on, bro!
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
I got the fuse #s from a different thread, but since no one had done anything with it...well you know the rest.
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
Originally Posted by Theta
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
I think the only thing that we need to vet (pun intended) is whether Engine Sound Management = Auto with no #41 keeps us out of CEL.
If it does, then I think with your contraption the ESM setting stays Auto, and your switch becomes the new ESM "Off". No more interaction with the car settings.
Or do I have this wrong?
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Until we know for sure, it's just a guess. I could just as easily be wrong.
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
This is important, as the idea relies on ESM still remaining active (and no CEL appearing, of course) in order to close the valve when the power is re-established to #41.
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
So just for kicks, I just went and actuated an NPP valve with my fingers.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
Last edited by xp800; Apr 4, 2014 at 10:05 PM.
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Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Very interesting! Thanks for checking that - keeps my hands clean while I'm working inside the car tonight. 
Interesting that it's not like a cutout with a motor that's geared to just open and close (or everywhere in between).
Interesting that it's not like a cutout with a motor that's geared to just open and close (or everywhere in between).
Instructor
Joined: Jan 2005
Posts: 138
Likes: 2
From: Canyon Country Ca.
So just for kicks, I just went and actuated an NPP valve with my fingers.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
Just find a clean method of snaking a couple wires from the drivers compartment into the fuse box wired in place of fuse #41 & have toggle switch near the driver.
Or I'm thinking just leave fuse 41 out and be done.
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Wireless tests were all abysmal failures across the board... Two days of testing, re-testing, using different frequencies, etc.
On to plan B, which is just as canyon said - a small SPST switch located on the driver's right knee (small) panel.
On to plan B, which is just as canyon said - a small SPST switch located on the driver's right knee (small) panel.
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
Very good - more points of data are a great thing!
Well, I guess it's time to tinker now that she's running again. The first hurdle will be what to use in the shallowness of the fuse box cover, but I have a few ideas. Second will be how to waterproof the box, but that also shouldn't be too hard.
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
Well, I guess it's time to tinker now that she's running again. The first hurdle will be what to use in the shallowness of the fuse box cover, but I have a few ideas. Second will be how to waterproof the box, but that also shouldn't be too hard.
The only downside to the remote relay is that you'd need to engage / disengage when the flaps are already open. Otherwise, you're cutting off their ability to do so. So you'd need to be over 1700rpm when you initially cut the power. Not a huge deal, but just pointing it out for others.
valves on the mufflers of the NPP. I have the NPP catback
A&A is installing it. (JUST A GUESS HERE on this)
But why can't I get the valve motor's from GM. I have the valve's but nothing to run them. Then power them up to open/close them with the mild to wild?
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
As I just wrote above, I did 2 days of extensive remote testing with 2 different remote relay devices (both brand name that I won't put here) with pretty much nothing to show for it.
I'd recommend running a simple switch into the cabin after the results I saw.
I'd recommend running a simple switch into the cabin after the results I saw.
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
I was thinking the mild to wild could be used to open and close the
valves on the mufflers of the NPP. I have the NPP catback
A&A is installing it. (JUST A GUESS HERE on this)
But why can't I get the valve motor's from GM. I have the valve's but nothing to run them. Then power them up to open/close them with the mild to wild?
valves on the mufflers of the NPP. I have the NPP catback
A&A is installing it. (JUST A GUESS HERE on this)
But why can't I get the valve motor's from GM. I have the valve's but nothing to run them. Then power them up to open/close them with the mild to wild?
I'll check and make sure they're 12v actuated, but most likely you'll just run an SPDT switch to open and close the valves.
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
So just for kicks, I just went and actuated an NPP valve with my fingers.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
It's a butterfly valve. There's a heavy return-to-open spring and the mechanical feel/damping of turning the servo/motor. So with no power there is effort to close it in winding up the spring and spinning the motor. Let it go and it opens only a little slowly; doesn't snap open. So my interpretation is that closed+cut power would allow them to open passively since it appears they want to open and stay open with no power. The motor works against/winds the return spring I think.
I think the switch would work and open the valves when power is cut.
The pipes I have 4 valves and no motors. I assume 2 I need on on my car but I want 2 more to them open and close. Anyone know what
voltage it takes to run or open close them? I think a mild to wild unit could work!
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
I thought it would be cool if the old mild to wild could be used.
Need to learn more to answer it!
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
I was thinking the mild to wild could be used to open and close the
valves on the mufflers of the NPP. I have the NPP catback
A&A is installing it. (JUST A GUESS HERE on this)
But why can't I get the valve motor's from GM. I have the valve's but nothing to run them. Then power them up to open/close them with the mild to wild?
valves on the mufflers of the NPP. I have the NPP catback
A&A is installing it. (JUST A GUESS HERE on this)
But why can't I get the valve motor's from GM. I have the valve's but nothing to run them. Then power them up to open/close them with the mild to wild?
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
I added Z06 cans to my 2008 base car. Used Orange Sunset Creations
(never get that name right)
they had a remote op vac pump to close them.
Need the open and close gotta have quiet at night
Team Owner
Joined: Mar 2005
Posts: 20,933
Likes: 905
From: salem OR
