Vacuum Lines - Ramblings/Ideas

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Fkyx
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Vacuum Lines - Ramblings/Ideas

Post by Fkyx »

Hello there!

Something I've always wanted to do with my car is tidy up the engine bay. We all know there are hoses everywhere in our engines, and one of the culprits is the mess of vacuum lines that make everything go round. I've been toying around with the idea of replacing, over time, the vacuum lines with hard lines that are routed a little more cleanly. I want to give the engine bay a personal touch.

So... I guess I have some questions for those of you knowledgeable in vacuum lines. First of all, is this even feasible? Given that all requirements are met, would the car run properly using metal lines over the silly vacuum tube that is stuff in there stock? Something tells me yes, it would, but I also don't know the requirements.

Given that it's feasible, would the inner diameter of the tubing matter? Looking at the beautiful vacuum line diagram that my personal idol, vrg3 posted http://www.surrealmirage.com/vrg3/vacuu ... vacuum.png there are definitely different sized lines meant for different purposes. But is it necessary for all of the lines to conform to those sizes? Or maybe be sized differently, but proportionately?

More questions to follow, given the answers to these ones.

Thanks!
Matthew
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
TurnNburn
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Re: Vacuum Lines - Ramblings/Ideas

Post by TurnNburn »

it should work just fine. In reality there is not a whole lot of air flow through most of those lines so I could see scaling down the hoses quite a bit. In the long run however I would expect to run into caking up of the lines. Except the big IAC to intake, that flows a good chunk of air and I wouldn't make the vacuum assist line to the brake booster a hard line, it would still need to be able to move as the engine pitches.

What would you use for lines?
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PhyrraM
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Re: Vacuum Lines - Ramblings/Ideas

Post by PhyrraM »

I can see a possible issue with the boost solenoid.

The factory duty cycles are chosen based on the system they are in - which includes the tubing sizes and flow, the restrictor pill size as a percentage of the tubing flow, the spring pressure and diaphragm size of the wastegate actuator, and the flowrate of the solenoid at various duty-cycles.

Any disruption in the balance of flow through the system may cause target boost to be off, or boost to rise faster or slower then the ECU is expecting. Of course, this is all assuming your still using a factory, or factory type, of boost control.
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Legacy777
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Re: Vacuum Lines - Ramblings/Ideas

Post by Legacy777 »

It's definitely feasible, but for the time and money you'll spend I think there are better things to spend your money on to make the car faster. I am mostly a function over form person, but do prefer things to look correct so I can certainly see things from your perspective.
Josh

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Fkyx
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Re: Vacuum Lines - Ramblings/Ideas

Post by Fkyx »

Thanks for the insight, guys! I'm running a TurboXS MBC, so that would alleviate some of the concern brought up by PhyrraM's response.

This is definitely down the line a ways, after I make some more power. Really, right now, the car is a blast to drive. But I always need to add my own personal touch to everything I own.

I've been playing around with the idea of using brass or copper tubing. Aluminum would suffice, too, but I think it would complicate things a little more than the other options. I understand that most of the lines would need to be able to flex with the engine pitch. The idea is to have short sections of silicone tubing somewhere in the mix to allow that flex without damaging the hard lines.

Thanks again, guys!
Matthew
Matthew aka F[b][color=red]k[/color][/b]yx
1991 Legacy Sport Sedan "Jillian" - [url=http://bbs.legacycentral.org/viewtopic.php?t=39548]EJ20G swap[/url]
Imprezafan93
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Re: Vacuum Lines - Ramblings/Ideas

Post by Imprezafan93 »

I used the hard lines on the intercooler in an attempt to clean thingsalittle-didnt help all that much. Its still a total mess but ill be fixing it again in the future. If anyone has a particular route design that worked stellar please share, because my setup looks a tad janky
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