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Secondary,take a long time to open, do they open fast while driveing?

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Secondary,take a long time to open, do they open fast while driveing?

Old 11-18-2005, 10:45 AM
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Secondary,take a long time to open, do they open fast while driveing?

hi, if I take the air cleaner off and look at the carb I have to almost redline the motor before the secondarys start to open, is that normal? do they open faster when driving? thanks
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Old 11-18-2005, 10:54 AM
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I'm surprised they're opening at all when you do that.
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Old 11-18-2005, 07:23 PM
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I could be totally off on this, but its my understanding that while the car is in park or neutral, basically under no load, theres not enough vacuum generated in the manifold to open the secondaries....Thats how i understand it anyway. Please someone correct me if im wrong.

Put the rear up on stands, put it in drive and try it again.

Bug
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Old 11-18-2005, 09:36 PM
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It is actuall because there is too much vacuum in the manifold that holds them closed. When you slam the throttle down under a load the vacuum drops to 0 and the secondaries open. If there is no load the engine will rev up fast enough to keed a vacuum and hold the secondaries closed.
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Old 11-18-2005, 09:54 PM
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Ahh, thanks for clearing that up. I was looking at it backwards I guess. I'm trying my best to figure this stuff out

Bug
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Old 11-18-2005, 09:59 PM
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Spring tension holds the secondary air valve closed, not vacuum.
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Old 11-18-2005, 10:01 PM
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The more I think of it yeah, that really makes alot more sense. Cause if you drive a car that is supercharged or whatnot and watch the gauge, when you step on it you see the needle come out of vacuum, past 0 and into boost. but when idlin or cruisin you're in the vacuum area.

Which poses another question, not one that really makes any difference, but on an NA car.. at WOT for example, you're out of vacuum in the manifold....is 0 the relative stopping measurement point? Or does it go on to create some minute measurement of boost? Sorry if this doesn't make any sense or is a stupid question. It sorta makes sense in my mind but don't know how to convey it properly.

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Old 11-18-2005, 10:04 PM
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Spring tension holds the secondary air valve closed, not vacuum.
Oh damn, well now i'm confused again lol
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Old 11-18-2005, 10:10 PM
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Originally posted by Apeiron
Spring tension holds the secondary air valve closed, not vacuum.
That is true @ sustained WOT. Transition from part-throttle to full throttle is a different story. You have a vacuum brake that has a 2-3 second delay built into it that allows for a smooth transition. A performance version will be drilled to allow for a 1 second pull-off.
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Old 05-15-2019, 12:58 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

.

Last edited by Zach/90\irocZ; 05-15-2019 at 02:36 PM.
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Old 05-15-2019, 01:03 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

WTF?!? You dig up a 14 year old thread to post information that isn't even related to the post? Turn that infinite scroll off
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Old 05-15-2019, 02:35 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

lmao I total was responding to a different thread smh
I was wonder about that I hate that how it does that now

but thanks brother
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Old 05-15-2019, 04:49 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

How do you turn that feature off?
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Old 05-15-2019, 08:45 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

Go to UserCP --> Edit options --> then it is a bubble to change under "Display thread options" --> Then click "save changes" at the bottom

I didn't mean to sound like an a ss either, sorry, lol
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Old 05-16-2019, 10:26 AM
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Re: Secondary,take a long time to open, do they open fast while driveing?

lmao your good
when I look up past post I was like this one don't look familiar and seen your post
but your good I should of pay attention more but yea didn't know it was a option to turn off

Originally Posted by scooter View Post
Go to UserCP --> Edit options --> then it is a bubble to change under "Display thread options" --> Then click "save changes" at the bottom

I didn't mean to sound like an a ss either, sorry, lol
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Old 05-16-2019, 10:33 AM
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Re: Secondary,take a long time to open, do they open fast while driveing?

I'm just curious to know if opie ever blew up his engine by revving it to redline while looking to see if the carb secondaries would open.
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Old 05-16-2019, 04:34 PM
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Re: Secondary,take a long time to open, do they open fast while driveing?

Nope, I still have the car all these years later, It now runs a Nice Black coated 650 DP.
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