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Size Of Hose From Boost Controller, Makes A Difference?

DriftinThruLife

By DriftinThruLife,
in Engines & Forced Induction

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DriftinThruLife Enthusiast

DriftinThruLife

Posted
Posted

Hi People.

My question is, does the diameter or width of the hose which goes from the boost controller (manual) to turbo make a difference?

I have been changing some factory hoses with silicon hoses, and for this particular hose... when i took it out and looked at the inner size of the hose (the hole) it didn't exactly match up with the sizes of the silicon hoses I had.

I tried putting a smaller size (this was very tight, and I took it off just incase it would split at where I had managed to connect it) and I tried a size that was slightly larger.

When i pressed the accelerator, the boost guage seemed to react the same for the thinner or wider hose.From this I assumed it didn't really matter.

When I started the engine though...it sounded a bit different. It didn't seem to be as loud. When I took it for a drive....(well it's kinda hard to describe) but the boost guage was behaving the same (if not going up higher) but the car seemed to lag slightly?

SO BASICALLY, Does the inner diammeter/width of the hoses going in or out of the boost controller make a difference? I assume it would, as it's controlling the air pressure right? So a wider hose would have the same amount of air at less pressure?

Bare in mind I have next to zero knowledge about turbos. Thanks in advance for any help.

lachlanw Veteran

lachlanw

Posted
Posted

yeah there is probably a reason why all good boost controllers come with different sized lines . 6 mm for boost sorce and to solenoid and 4 mm for boost reference signal

PM-R33 Grand Master

PM-R33

Posted
Posted (edited)

Once the line is under pressure there is no difference. It's the difference in time it takes to pressurize that line that is important. The difference in time it takes is the amount of volume between the two sources that air has to occupy. (Think of a bigger example as intercooler piping and the turbo needing to pressurize all the piping before it gets to the intake).

For a boost controller this can mean a spike if it takes to long for the line to pressurize and then the boost controller to bleed off the air it needs. We are talking fractions of a second in such a small line. So if a line is really long or really large in diameter, it can make a difference and cause a spike that would not have occured if the line was shorter or smaller. With the diameter of most vacuum lines used for boost controllers, you aren't talking much. For example going from a 4mm hose to a 6mm hose would be the equivalent volume as say another extra 5cm in line of the 4mm hose (For example. If you want to do the calcs for the exact amount of a given length you can)

So in other words unless you are using 1/2" vacuum line for your boost controller it aint going to change sweet f**k all.

Keep your lines short is the main thing, dont have them looping half way around the engine bay and then into the car through the dash if you want your boost controller to work well.

Edited by PM-R33
R31Nismoid Grand Master

R31Nismoid

Posted
Posted

It can make a difference. Length indeed makes a difference as well. I've seen it first hand.

Length and diameter over say 2-3 meters (seen people hide bleeders on drivers side of the engine bay) etc etc.

Being the hose gets hotter and expands more and more the larger base you start from.

Well... that's my guess anyway :)

SECURITY Grand Master

SECURITY

Posted
Posted

depends on how thick the walls are. the thicker, the better it will perform in terms of being prone to kinking and closing up on itself in vacuum. ive seen plenty of the thin walled hoses close up on themselves.

size matters boys :)

DriftinThruLife Enthusiast

DriftinThruLife

Posted
  • Author
Posted

Hmmm, you know what...I reckon I'll put up a pic of the 2 hoses side-by-side....then i'll let you decide.

SECURITY...that's a scary a** display pic you have man...wouldnt wanna meet him in a dark alley.

Lukas33....mmm that's a sexy a** display pic you have man....they wouldn't wanna meet me in a dark alley.

Lukas 33 Proficient

Lukas 33

Posted
Posted
haha sorry mate. had to.

as long as theyre short they should be no problem.

HAHAHA YES!!! i was going to point that out but thought I should keep my serious hat on. Then you went and did it :) Top work :laugh:

Yeh well after your line busting like that Phil Im surprised you didn't recommend it, Must admit though it does make you engine bay look the sex.

Yeh I have a Profec B Spec II aswell and its about 20cm from cooler pipe to solenoid. So its very short. So as long as its long enough to fit in the gap but not too long as it doesn't get pressurised/hard quick enough AND as long as it is thick enough. It should hold any load/boost without spiking nicely

Lukas 33 Proficient

Lukas 33

Posted
Posted
pussy, shoulda kept stuck into it! :ninja:

HAHAHA Stock internal 25 on 2.5 bar......harden up phil.

He is not joking about everything being braid either. He has braided electrical wiring going to the ceiling light. He has even made a steering wheel cover out of braid. Rumor has it that he has redone all the plumbing in his house with braid.

DriftinThruLife Enthusiast

DriftinThruLife

Posted
  • Author
Posted

Hmm looks like I have to change it back or get another one anyway.

It started making a high pitched whitsling noise today. And I'm guessing that's either because of a hole in it, or crack, or the plastic ties aren't tight enough but yeh....some sort of leak.

Oh well, back to the drawing board.

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