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Cleaning up vacuum mess on CCC Q-Jet

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Old Sep 11, 2008 | 08:35 AM
  #1  
r0nin89's Avatar
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From: Point Pleasant, NJ
Car: 1987 Chevy Stepside
Engine: 350 TBI w/ a Cam
Transmission: 3 Speed Stick w/ granny low
Cleaning up vacuum mess on CCC Q-Jet

I cant help but be annoyed by the fact there theres 30 y splitters and 20 diaphrams on all the vacuum accessories on my car. It really seems like a great deal are unneeded. I'm mean is it really required to have 2 or 3 vacuum diaphrams on my evap cannister?

Are there any articles or sites where they can explain what most of it does or even what I can delete and route more simplistically?

I mean my tbi truck runs on like 5 vacuum lines, why does a carb which is suppose to be more simplistic have so damn many?
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Old Sep 11, 2008 | 10:24 AM
  #2  
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
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Axle/Gears: 3.54 Dana 44
Re: Cleaning up vacuum mess on CCC Q-Jet

The ECM is smarter on your TBI and can control more things electrically. The carb ECM is a dinosaur, so a lot of systems are controlled by vacuum. You only need the vacuum lines if you want the things they operate to actually work.
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Old Sep 11, 2008 | 11:59 AM
  #3  
r0nin89's Avatar
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From: Point Pleasant, NJ
Car: 1987 Chevy Stepside
Engine: 350 TBI w/ a Cam
Transmission: 3 Speed Stick w/ granny low
Re: Cleaning up vacuum mess on CCC Q-Jet

Yeah bu things like evap canister for instance. Why do there need to be two diaprams controlling the in and out vaccuum lines? Cant I just put one line into it and one line into the carb? The computer doesnt control anything there. It just seems like its redundant lines.
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Old Sep 11, 2008 | 12:53 PM
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Re: Cleaning up vacuum mess on CCC Q-Jet

If it's factory, it's there for a reason. Just because it looks messy doesn't mean it's unnecessary. Please don't start pulling vac parts for aesthetic reasons. People often wind up with really poor running cars and odd problems when that happens.
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Old Sep 11, 2008 | 01:13 PM
  #5  
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From: Battle Ground, WA
Car: 1986 Chevy Silverado
Engine: 350 Crate
Transmission: Turbo 400 w/ shift kit
Axle/Gears: dana60/corp14 4.10 gears
Re: Cleaning up vacuum mess on CCC Q-Jet

Unless you are gonna rip out all the elctronics and go to just a good ole engine then keep them. I know it sucks but 327 is right they are there for a reason.

Thanks,

Trey

---------------- Now playing: Kid Rock - Early Mornin' Stoned Pimp via FoxyTunes
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Old Sep 13, 2008 | 10:11 PM
  #6  
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Car: 87 Camaro Z-28
Engine: 305 LG4 w/ E4ME carb
Transmission: 700R4
Axle/Gears: 2.73
Re: Cleaning up vacuum mess on CCC Q-Jet

you can get quite a bit from a haynes manual (info in diferent chapters). the different lines help pull gas vapors from different parts of the carb. chevy needed to lower release of unused gas into air and increase fuel milagae. how's the truck running?
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Old Sep 14, 2008 | 01:42 AM
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Apeiron's Avatar
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From: Mercedes Norte, Heredia, Costa Rica
Car: 1984 Z28 Hardtop
Engine: 383 Carb
Transmission: 4L60
Axle/Gears: 3.54 Dana 44
Re: Cleaning up vacuum mess on CCC Q-Jet

Originally Posted by r0nin89
Yeah bu things like evap canister for instance. Why do there need to be two diaprams controlling the in and out vaccuum lines? Cant I just put one line into it and one line into the carb? The computer doesnt control anything there. It just seems like its redundant lines.
No the computer doesn't control anything there, but something has to make sure that the canister is only purged under the appropriate running conditions.
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Old Sep 14, 2008 | 08:40 PM
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Re: Cleaning up vacuum mess on CCC Q-Jet

If you want to rip everything off but keep it computer controlled you can do so. The only "necessary" vacuum lines coming off the carb are:

1. To the VAC sensor (firewall mounted, if memory serves).

2. To the EGR system.

3. To the PCV valve, power brake booster (big 3/8" lines)

4. To the HVAC control system, although I believe this line comes off the vacuum port screwed into the intake manifold just behind the carb.

5. The short line going to the vacuum canister on the pass. side of the carb.

Plug any unused vacuum ports on the carb. Leave ALL electrical connections on the carb in place.

On the charcoal canister leave the line coming from the fuel tank in place and leave the rest of the ports open.

You can also remove the smog pump and all related lines as well (make sure to plug any open ports so you don't have an exhaust leak). ECM doesn't monitor this system either.

The combination of these two can really clean up the look of the engine bay considerably.

Last edited by Damon; Sep 14, 2008 at 08:45 PM.
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Old Mar 14, 2011 | 03:21 AM
  #9  
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From: Salt Lake City, Utah
Car: 1988 camaro "SS"/ 1991 305/T5
Engine: 383 LT1 in progress/LT1TBI 355 soon
Transmission: Probuilt 700R4 3600 stall/ T5
Axle/Gears: Moser axles, 3.42 Eaton Posi
Re: Cleaning up vacuum mess on CCC Q-Jet

I know I'm dragging up an old post but I'm helping a friend clean up their 82 bird's engine bay. It has the quad carb on it and we are trying to get the engine bay to look "similar" to mine. Damon, you would happen to have any pics of what you're talking about?
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Old Mar 22, 2011 | 02:51 PM
  #10  
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Car: 85 Firebird & Grand Prix GXP
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Re: Cleaning up vacuum mess on CCC Q-Jet

Dittos
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Old Mar 23, 2011 | 04:00 AM
  #11  
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Re: Cleaning up vacuum mess on CCC Q-Jet

Just start with dumping the A.I.R. system. That alone makes a huge difference.
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Old Apr 6, 2011 | 08:47 AM
  #12  
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Car: 87 Camaro
Engine: 305 LG4 (H)
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Re: Cleaning up vacuum mess on CCC Q-Jet

Are you really looking under your hood that much? Leave it alone, its all there for a reason.

Originally Posted by DoubleV
Just start with dumping the A.I.R. system. That alone makes a huge difference.
Difference in what? What is more important to you guys? Underhood appearance or underhood functionality? Sounds like the former to me.....
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Old Apr 6, 2011 | 05:06 PM
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Re: Cleaning up vacuum mess on CCC Q-Jet

Originally Posted by Camaro305SB
Are you really looking under your hood that much?
Yeah pretty much. Most of us are pretty proud of our cars and like to show it off as much as possible, especially at car cruises and such. The AIR system looks like an abomination.

Leave it alone, its all there for a reason.
What reason would that be? Sleightly better emissions during a cold start? Whoopti-freaken-do. Who effen cares.

Difference in what? What is more important to you guys? Underhood appearance or underhood functionality? Sounds like the former to me.....
Apparently you don't work on your own car ( or show it off ). If you did you'd notice how much more difficult it is to work on with all that $hit in the way. The AIR system is also prone to failure and is just another thing to have to concern yourself with all for no gain. A car will NEVER run worse without an air pump, but CAN run worse with one if it's not functioning properly.

So yeah, unless you have a visual inspection in your area, the AIR system is total garbage in every way you could imagine. That's why I suggested dumping it. To my knowledge, no ones EVER regreted removing it and in fact are thrilled with it's removal.

Last edited by DoubleV; Apr 6, 2011 at 05:39 PM.
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Old Sep 2, 2025 | 06:00 AM
  #14  
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From: MN
Car: 1987 trans-am
Engine: 350
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Re: Cleaning up vacuum mess on CCC Q-Jet

This has been helpful. I get people are on both sides, but alot of it does seem unnecessary. I want to get rid of egr but dont wanna cause any problems on the computer. Have a manual coming today so I can figure out what I can clean up.
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