NPP fuse pull trick/result
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
lol just saw this thread. Why not just hook this up to fuse 41 and switch it on and off when you want? There are a couple of other products like this when I was into car pc's, but it's all the same concept. Switchable fuse.
http://www.quadratec.com/products/13029_200.htm
I read above pulling fuse in an auto makes it sound horrible from behind. Is this the same as a manual?
http://www.quadratec.com/products/13029_200.htm
I read above pulling fuse in an auto makes it sound horrible from behind. Is this the same as a manual?
An auto and manual should not sound different in V8 mode with NPP valves open. Unless the auto owner pulled fuse 32 as well and then the sound from the rear would sound like a$$ in V4 mode since it spends more time there. But that said, auto and manual should sound no different when operating/configured the same way.
Last edited by xp800; Oct 14, 2014 at 07:43 AM.
Pro
Joined: Nov 2013
Posts: 686
Likes: 11
Interesting. That would require powering them at all times. This is the exact issue that has remained unresolved to my knowledge. You will see this discussed earlier in this thread as well, but in the context of manual control. The switching is on the low side, so you can't override the switching by pulling switched power from another circuit.
On a simpler solution, is there a reason inserting plugs in the outer tips wouldn't work? There's no flow through them with the valves closed; all the flow is through the inner tips. Not sure if the additional back pressure would do anything other than reduce power a small amount. It may take some doing to keep them in place in race conditions.
An NPP-pon?
On a simpler solution, is there a reason inserting plugs in the outer tips wouldn't work? There's no flow through them with the valves closed; all the flow is through the inner tips. Not sure if the additional back pressure would do anything other than reduce power a small amount. It may take some doing to keep them in place in race conditions.
An NPP-pon?
Yea. Looking at it. To try keep it shut i noticed no power is open
Leeds.io
Joined: Sep 2003
Posts: 4,604
Likes: 409
From: White Mountains
St. Jude Donor '14-'15-'16
NCM Sinkhole Donor
Thanks for the info. Can the C7 be done like the C6 by adding a toggle switch to turn on off when ever you want? I did my last 3 C6s this way. Only cost around 15 bucks depending on what switch you use. Like this?
http://forums.corvetteforum.com/c6-c...with-pics.html
http://forums.corvetteforum.com/c6-c...with-pics.html
Sorry if I'm being the C7 NPP n00b here.
Best,
Gene
Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Can someone explain to me exactly why the above doesn't work? I understand that "circuit closed" will not result in valves closed all the time. However wouldn't this switch be exactly the same as removing or replacing the fuse? Circuit open and no more 1700rpm issues. Circuit closed and no potential for highway drone? I don't understand why all the fuss and not just go with the above? If the issue is that it's in the fuse box under the hood that's not an issue. I, may have, wired a fuse switch to the box under the hood on my C6Z that cut off my license plate light and side markers.
Sorry if I'm being the C7 NPP n00b here.
Best,
Gene
Sorry if I'm being the C7 NPP n00b here.
Best,
Gene
The only difficulty lies in routing wiring into the fuse box, which can be accomplished with O-rings and quick disconnects (and an in-line fuse).
Leeds.io
Joined: Sep 2003
Posts: 4,604
Likes: 409
From: White Mountains
St. Jude Donor '14-'15-'16
NCM Sinkhole Donor
Do you, or anyone else, have a DYI photo thread on the best way to do the install with said O-rings...ect?
Thank you for all the research and work you and the others have put into this.
Best,
Gene
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Tech Contributor
Joined: Jan 2006
Posts: 4,761
Likes: 240
From: Saint Louis MO
St. Jude Donor '14-'15
Thank you! Additionally couldn't one program the system to keep the valves closed in all settings. Then set the system to Auto. This might make a loud to stealth switch out of the fuse switch, no?
Do you, or anyone else, have a DYI photo thread on the best way to do the install with said O-rings...ect?
Thank you for all the research and work you and the others have put into this.
Best,
Gene
Do you, or anyone else, have a DYI photo thread on the best way to do the install with said O-rings...ect?
Thank you for all the research and work you and the others have put into this.
Best,
Gene
I don't have pictures, but can take some in a few weeks for you. Essentially, you can run 2 14ga sheathed hook-up wires in through a small O-ring (so, one in, one out to be completely waterproof), then terminate into a neutered fuse (cut through the center). A small drill bit works wonders for this task.
Then, simply run the wiring into the car using the same old 'left of the clutch pedal' hole, and choose where to mount your switch. Install a properly-rated fuse in-line with one the wires, and you have an easy on/off solution!
Instructor
Joined: Dec 2013
Posts: 101
Likes: 0
From: Austin TX
LT headers, no cats, etc...
Interestingly, my car (perhaps from the dramatically increased torque demand) is ALWAYS OPEN in track mode, sport mode seems barely more quiet at idle, but it's essentially always "melt your face open" as well. Just mentioning this as there is potential that the changes made to my tune might be applicable to this groups needs. You cannot mistake open/closed in my car, the difference is STAGGERING.
Leeds.io
Joined: Sep 2003
Posts: 4,604
Likes: 409
From: White Mountains
St. Jude Donor '14-'15-'16
NCM Sinkhole Donor
FWIW I set my Z06's exhaust sound settings to track for all modes. I don't experience any type of change at 1,700. It does sound like it's completely open all the time.
Another new Z06 owner, who traded in his C7 for it, said the NPP seems to work differently and stay open.
I have no science on this at this time but it's what I've experienced. Just wanted to pass it along.
Best,
Gene
Another new Z06 owner, who traded in his C7 for it, said the NPP seems to work differently and stay open.
I have no science on this at this time but it's what I've experienced. Just wanted to pass it along.
Best,
Gene
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
FWIW I set my Z06's exhaust sound settings to track for all modes. I don't experience any type of change at 1,700. It does sound like it's completely open all the time.
Another new Z06 owner, who traded in his C7 for it, said the NPP seems to work differently and stay open.
I have no science on this at this time but it's what I've experienced. Just wanted to pass it along.
Best,
Gene
Another new Z06 owner, who traded in his C7 for it, said the NPP seems to work differently and stay open.
I have no science on this at this time but it's what I've experienced. Just wanted to pass it along.
Best,
Gene
Gene,
Thank you for adding some useful new insights and a bit of new excitement for us NPP geeks.
Just so I'm clear on what you've done... You have gone into Engine Sound Management and set it to Off. This is what I interpret from your 'race mode' comment.
The best way to notice the behavior anomaly with ESM off, if it exists in the Z06, is to lazy shift from 3 into 4 so that the revs fall well below 1500rpm. Then slowly tip into the throttle, and then right at 1700rpm the sound should go from muted to V8 glory in an instant.
Who knows... Maybe the Corvette engineers have been reading this thread and decided to have off=off finally.
Burning Brakes
Joined: Oct 2009
Posts: 1,004
Likes: 68
From: Cincinnati OH
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
Turns out that the Z06 has unique NPP settings! Maybe this will find it's way to the Singray NPP?
Thanks to occar:
https://www.corvetteforum.com/forums...post1588492970
Thanks to occar:
https://www.corvetteforum.com/forums...post1588492970
Racer
Joined: Jun 2014
Posts: 277
Likes: 5
From: Mill Creek Washington
Can someone clarify the 1700rpm issue for me?
Are the NPP valves closed below 1700rpm regardless of ESM or Drive mode selection?
I want to idle loudly! and have lots of pops and burbles like i used to, right now I just leave it in sport mode but I feel my C6 with mild to wild was much louder.
Are the NPP valves closed below 1700rpm regardless of ESM or Drive mode selection?
I want to idle loudly! and have lots of pops and burbles like i used to, right now I just leave it in sport mode but I feel my C6 with mild to wild was much louder.
Thread Starter
Drifting
Joined: Jun 2007
Posts: 1,425
Likes: 238
From: Macomb MI
Can someone clarify the 1700rpm issue for me?
Are the NPP valves closed below 1700rpm regardless of ESM or Drive mode selection?
I want to idle loudly! and have lots of pops and burbles like i used to, right now I just leave it in sport mode but I feel my C6 with mild to wild was much louder.
Are the NPP valves closed below 1700rpm regardless of ESM or Drive mode selection?
I want to idle loudly! and have lots of pops and burbles like i used to, right now I just leave it in sport mode but I feel my C6 with mild to wild was much louder.
Item #8 in the first post explains the behavior best. The 1700RPM issue does not happen at idle, it happens on manual cars on upshifts or driving in upper gears when RPMs fall below 1700RPM. Then the valves close and then reopen at 1700RPM when accelerating.
Racer
Joined: Sep 2014
Posts: 366
Likes: 175
From: North Carolina
I don't know anything about cars. I tried doing a google search for fuse 42 for 2015 corvettes but where is it located? Are the fuses labeled by number when you find it? Just wanna make sure I pull the right one.
Burning Brakes
Joined: Oct 2009
Posts: 1,004
Likes: 68
From: Cincinnati OH
The fuse is in the box under the hood on the passenger side. There are pics in the thread about location or in the manual.