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Old 03-19-2014   #1
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default NPP Exhaust Valve Controls

NPP Exhaust Control Valves help control resonance without the weight and backpressure of a resonator. However the use of engine vacuum can also cause the valves to open during low vacuum or high MAP conditions. Typically, this happens on inclines causing the valves to crack open increasing resonance. I recently had the opportunity to find an NPP Retrofit kit by Nakid Parts. However, in trying to install it, it didn't work well or not at all. Everything checked out and it did work when using a brake bleeder as a vacuum source. When applying engine vacuum however the exhaust control valves remained in whatever position they were in with engine start. Everything checked out. NakidParts checked the unit and found it to operate properly. They stated that they had 800 units in operation including one for Jay Leno. Maybe it's an issue w the LT-5 v an LS-3 or LS-7.
Reviewing the electrical, pneumatic circuits there was no reason why it shouldn't work. But it just didn't.as Sherlock Holmes would say to Watson,

'How often have I said to you that when you have eliminated the impossible, whatever remains, however improbable, must be the truth?'

It's now clear the solenoid used w the NPP in a Box Retrofit kit has an issue, at least, w LT-5 engine vacuum. mike100 has done his own NPP control using a GM EGR solenoid. I decided to try this solenoid in place of the one used for NIAB retrofit.
So here's a video showing the operation of the NPP retrofit BUT using a GM EGR SOLENOID in place of the stock NIAB solenoid.

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Last edited by XfireZ51; 03-19-2014 at 11:23 PM.
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Old 03-20-2014   #2
mike100
 
Join Date: Feb 2011
Location: San Marcos CA
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Default Re: NPP Exhaust Valve Controls

Already posted on the other forum, but glad to see you verified function of the solenoid I recommended in the write-up for the next HoTB newsletter.
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Old 03-20-2014   #3
XfireZ51
 
Join Date: May 2007
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Default Re: NPP Exhaust Valve Controls

Quote:
Originally Posted by mike100 View Post
Already posted on the other forum, but glad to see you verified function of the solenoid I recommended in the write-up for the next HoTB newsletter.
Yep Mike. Works great. Valves snap open and shut smoothly. I happened to look at the remnants of my AIR equipment and noticed that the solenoid used there is the same or very similar. However, it does have a vent at the bottom that leads to the AIR valve.
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1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX
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Old 03-20-2014   #4
efnfast
 
Join Date: Nov 2011
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Default Re: NPP Exhaust Valve Controls

Well, ain't that cool!
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Old 03-20-2014   #5
Schrade
 
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Default Re: NPP Exhaust Valve Controls

Quote:
Originally Posted by mike100 View Post
Already posted on the other forum, but glad to see you verified function of the solenoid I recommended in the write-up for the next HoTB newsletter.

There's another forum? (that's NOT run by anal-orifeces? )

--------------------------------------------------------------------------------------------------------

I'm still thinkin' on a way to remotely actuate the valves on the PE pipes I got from Jeff [Shrek]; either mechanically, by cable, or vacuum actuation, maybe with the secondary port actuators somehow, which tested functional, before I removed them after top end work...



Either way would call for affixing some sort of arm onto the valve controller knobs:

__________________
I'm getting my snappics / threads removed blindly as fast as I can, to get in compliance with copyright / license TOS on the boards here (lots of FSM pages and other copyright / license violations on my part; sorry guys). And thanks to all the guys who didn't whine when I posted those FSM copyrighted / licensed stuff in my threads...

( :thumbsup: [b]and to think I complied with a mod's request to delete a pic of him in a Challenge Car in NCM Museum, so he wouldn't get in hot water)[/b]

Thanks to several guys here for sending parts FREE; BearlyFlying, WeGone, Geezer, GoldCylon, and more there, TonyD, mike100, fletchusmc...

1990 #2794; 4L60e Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless, Power Effects 3"

[IMG]https://lh5.googleusercontent.com/-GHpfzty7DVU/UQn-0Ru2xAI/AAAAAAAAA14/08mz1p4QLD4/s445/Screenshot-5.png[/IMG]
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Old 03-22-2014   #6
WARP TEN
 
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Default Re: NPP Exhaust Valve Controls

Quote:
Originally Posted by Schrade View Post
There's another forum? (that's NOT run by anal-orifeces? )

--------------------------------------------------------------------------------------------------------

I'm still thinkin' on a way to remotely actuate the valves on the PE pipes I got from Jeff [Shrek]; either mechanically, by cable, or vacuum actuation, maybe with the secondary port actuators somehow, which tested functional, before I removed them after top end work...



Either way would call for affixing some sort of arm onto the valve controller knobs:

You might be able to adapt the QTP motors and wiring to the PE valves. Depends on how much torque it takes to turn the knobs I suppose; also the QTPs only turn the cutout valves 90 degrees. QTPs website has some pdfs on the components but I didn't see info on motor torque etc. --Bob
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Last edited by WARP TEN; 03-22-2014 at 03:47 PM.
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Old 03-23-2014   #7
XfireZ51
 
Join Date: May 2007
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Default Re: NPP Exhaust Valve Controls

Have run into a glitch that really has me scratching my head. The M2W remote fob works just fine when the motor is running BUT when the vacuum solenoid and wireless receiver are powered using my little lawn tractor battery as a stand in. However, once I transfer power and ground over to the car BATT and ground, it won't work with engine running. With ignition ON, but no engine start, I can hear the solenoid clicking as I press the fob. Once I start the motor, NADA. Appears that no signal is getting through to the wireless.
At this point, I'm about to give up on the fob and install a ground interrupt switch in the console. I don't see the real value of the fob. It's not like I am going to be walking around the car while it idles and I click the fob on and off.
A toggle switch in the console should work just fine as you drive.
Maybe one of you EE geniuses can come up w a good solution. I may try it just to solve the mystery but otherwise, I've spent way too much time messing w this thing. Altho I definitely want to be able to control the opening and closing of the exhaust valves.
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Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
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Old 03-23-2014   #8
Schrade
 
Join Date: Dec 2012
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Default Re: NPP Exhaust Valve Controls

Quote:
Originally Posted by WARP TEN View Post
You might be able to adapt the QTP motors and wiring to the PE valves. Depends on how much torque it takes to turn the knobs I suppose; also the QTPs only turn the cutout valves 90 degrees. QTPs website has some pdfs on the components but I didn't see info on motor torque etc. --Bob
THanks for the lead there Mr. B - will do some reading there...


Dom; any chance that you could PhotoChop the wiring diagram with your wiring chopped into the schematic???

Snappics do show things in a different perspective, AND YOU MIGHT SEE THE PROBLEM / SOLUTION AS YOU MAP IT OUT THERE...

...and, try POWER from lawnmower, with GROUND on car, and then POWER from car, GROUND on mower.................................
Quote:
Originally Posted by XfireZ51 View Post
Have run into a glitch that really has me scratching my head. The M2W remote fob works just fine when the motor is running BUT when the vacuum solenoid and wireless receiver are powered using my little lawn tractor battery as a stand in. However, once I transfer power and ground over to the car BATT and ground, it won't work with engine running. With ignition ON, but no engine start, I can hear the solenoid clicking as I press the fob. Once I start the motor, NADA. Appears that no signal is getting through to the wireless.
At this point, I'm about to give up on the fob and install a ground interrupt switch in the console. I don't see the real value of the fob. It's not like I am going to be walking around the car while it idles and I click the fob on and off.
A toggle switch in the console should work just fine as you drive.
Maybe one of you EE geniuses can come up w a good solution. I may try it just to solve the mystery but otherwise, I've spent way too much time messing w this thing. Altho I definitely want to be able to control the opening and closing of the exhaust valves.
__________________
I'm getting my snappics / threads removed blindly as fast as I can, to get in compliance with copyright / license TOS on the boards here (lots of FSM pages and other copyright / license violations on my part; sorry guys). And thanks to all the guys who didn't whine when I posted those FSM copyrighted / licensed stuff in my threads...

( :thumbsup: [b]and to think I complied with a mod's request to delete a pic of him in a Challenge Car in NCM Museum, so he wouldn't get in hot water)[/b]

Thanks to several guys here for sending parts FREE; BearlyFlying, WeGone, Geezer, GoldCylon, and more there, TonyD, mike100, fletchusmc...

1990 #2794; 4L60e Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless, Power Effects 3"

[IMG]https://lh5.googleusercontent.com/-GHpfzty7DVU/UQn-0Ru2xAI/AAAAAAAAA14/08mz1p4QLD4/s445/Screenshot-5.png[/IMG]
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Old 03-23-2014   #9
XfireZ51
 
Join Date: May 2007
Location: Chicagoland, IL
Posts: 9,708
Default Re: NPP Exhaust Valve Controls

OK. Decided to forego the fob. However, I have it connected so if I ever figure out what the issue is, I can use the fob as an alternative. Frankly, I don't see myself wanting to close or open the exhaust valves when I am outside of the car with motor running.

Here's my solution. BTW it was idling like that and THEN I realized I had left off the brake booster hose AND the vacuum supply to the Fuel Pressure Regulator. DOH!

__________________
[SIGPIC][/SIGPIC]Former Membership Chairman
Former ZR-1 Registry - BOD
1972 Corvette 4speed base Coupe SOLD long time ago
1984 Corvette Z-51/4+3 SOLD
1992 Corvette ZR-1 Aqua/Gray #474 SOLD
1992 Corvette ZR-1 Black Rose/Cognac #458
2014 Honda VFR Interceptor DX

Last edited by XfireZ51; 03-23-2014 at 08:59 PM.
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Old 03-23-2014   #10
Schrade
 
Join Date: Dec 2012
Location: NC
Posts: 1,786
Default Re: NPP Exhaust Valve Controls

Quote:
Originally Posted by XfireZ51 View Post
OK. Decided to forego the fob. However, I have it connected so if I ever figure out what the issue is, I can use the fob as an alternative. Frankly, I don't see myself wanting to close or open the exhaust valves when I am outside of the car with motor running.

Here's my solution. BTW it was idling like that and THEN I realized I had left off the brake booster hose AND the vacuum supply to the Fuel Pressure Regulator. DOH!

So your vacuum was off when you plugged in the actuator?

Doesn't that warrant a re-try?

__________________
I'm getting my snappics / threads removed blindly as fast as I can, to get in compliance with copyright / license TOS on the boards here (lots of FSM pages and other copyright / license violations on my part; sorry guys). And thanks to all the guys who didn't whine when I posted those FSM copyrighted / licensed stuff in my threads...

( :thumbsup: [b]and to think I complied with a mod's request to delete a pic of him in a Challenge Car in NCM Museum, so he wouldn't get in hot water)[/b]

Thanks to several guys here for sending parts FREE; BearlyFlying, WeGone, Geezer, GoldCylon, and more there, TonyD, mike100, fletchusmc...

1990 #2794; 4L60e Stage V by RPM Transmission, TCI Dedicated TCM, OBX Stainless, Power Effects 3"

[IMG]https://lh5.googleusercontent.com/-GHpfzty7DVU/UQn-0Ru2xAI/AAAAAAAAA14/08mz1p4QLD4/s445/Screenshot-5.png[/IMG]
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