Jump to content
SAU Community

Recommended Posts

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.

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

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

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 :)

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 :)

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.

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

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.

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.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Yeah, it's getting like that, my daughter is coming over on Thursday to help me remove the bonnet so I can install the Carbuilders underbonnet stuff,  I might get her to give me a hand and remove the hardtop, maybe, because on really hot days the detachable hardtop helps the aircon keep the interior cool, the heat just punches straight through to rag top I also don't have enough hair for the "wind in the hair" experience, so there is that....LOL
    • Could be falling edge/rising edge is set wrong. Are you getting sync errors?
    • On BMWs what I do because I'm more confident that I can't instantly crush the pinch welds and do thousands of USD in chassis damage is use a set of rubber jacking pads designed to protect the chassis/plastic adapter and raise a corner of the car, place the aforementioned 2x12 inch wooden planks under a tire, drop the car, then this normally gives me enough clearance to get to the front central jack point. If you don't need it to be a ramp it only needs to be 1-1.5 feet long. On my R33 I do not trust the pinch welds to tolerate any of this so I drive up on the ramps. Before then when I had to get a new floor jack that no longer cleared the front lip I removed it to get enough clearance to put the jack under it. Once you're on the ramps once you simply never let the car down to the ground. It lives on the ramps or on jack stands.
    • Nah. You need 2x taps for anything that you cannot pass the tap all the way through. And even then, there's a point in response to the above which I will come back to. The 2x taps are 1x tapered for starting, and 1x plug tap for working to the bottom of blind holes. That block's port is effectively a blind hole from the perspective of the tap. The tapered tap/tapered thread response. You don't ever leave a female hole tapered. They are supposed to be parallel, hence the wide section of a tapered tap being parallel, the existince of plug taps, etc. The male is tapered so that it will eventually get too fat for the female thread, and yes, there is some risk if the tapped length of the female hole doesn't offer enough threads, that it will not lock up very nicely. But you can always buzz off the extra length on the male thread, and the tape is very good at adding bulk to the joint.
    • Nice....looking forward to that update
×
×
  • Create New...