Installing an npp
Instructor
Joined: Dec 2014
Posts: 226
Likes: 14
From: Houston TX
They default to open when the fuse is pulled or the electronics break. When you start the car, they are wide open then close quickly upon start.
SO to answer your question. LOUD!!!
SO to answer your question. LOUD!!!
Last edited by 09_BSM_Z51; Oct 11, 2016 at 07:19 PM.
Race Director
Joined: Apr 2000
Posts: 15,344
Likes: 4,009
From: Texas
Not if they're factory unless someone modified them. Until commanded after start-up, the butterflies are open. With no power or vacuum applied to the solenoid the butterflies will remain open.
Le Mans Master
Joined: Oct 2014
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From: Atlanta GA
Dave
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Verdad Gallardo
Race Director
Joined: Apr 2000
Posts: 15,344
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From: Texas
At rest and upon start-up, the butterflies are open.....always. After start-up....a second or so once vacuum builds...the butterflies close *unless* you pull the fuse, add something like NPP in a Box, or have M2W set to keep them open.
In this pic, you can see the butterflies open. Obviously the car is off while I'm doing some work on it...
As you can clearly see, they are not normally closed. They close when commanded, typically at start-up, but that can be defeated as outlined above.
