To Blow Off Valve or not to Blow Off Valve??

[Bludger]

just dose and replace when failure occurs

[Lukezen27]

just dose and replace when failure occurs

Yeah I've decided to dose and that's it

aimre makes a good point, the cost seems about that same in the end anyway...

[Muzz]

Exactly, not running one youd never know worse off anyways.

[Muzz]

Sting, i dont have time to bicker with you on somthing as petty as this, this is the last time im going to reply.

A little bit of chatter from your charge pipes.

Where did you learn that the chatter is actually coming from the piping?
Is this solid info you’re sharing here, or are you stating what you think?

Garrett seems to think it’s from the compressor.

Oh dear. I completely meant and said that the charge pipes cause "chatter". I can take partial quotes out of context too.

Sorry man, here ill use your whole quote for ya.

Consider the forces involved between continuous operating in the surge region versus a little bit of chatter from your charge pipes filled with some boost.

You’re implying that surge from the throttle snapping shut, is less harmful then surge for other reasons. Are you not?
Do you know this for sure?

Your saying straight out “a little bit of chatter from the charge pipes filled with some boost”. If you infact know its not from the charge pipes, then why the hell say it?

Why not say it exactly how it is?
"Consider the forces involved between continuous operating in the surge region, versus seeing the surge region for a split second every gear change."

Oh yes, that’s right, it dosnt help support your views, better to say it in a way that gives the impression that surge from closing the throttle is less damaging.

Just a little bit of chatter from the pipes filled with some boost? Couldn’t think of a better way to make it sound harmless, great job!

Im not taking ANYTHING out of context, im using your quote in the exact context you said it bud.
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Generalized FAQ answers is not SOLID PROOF of anything.

Exactly what are you trying to say with this statement?

Are you trying to say Garrett doesn’t actually have proof that operating in surge conditions is bad for their turbos? Did they go and put false info into there FAQ and turbo tech sections yeah? There making misleading statements like the one below are they?

You're shooting down my interpretation of garrett's FAQ only to try to bend it in your direction. Please...

Bend it my direction? Are you ****ing kidding? This is a joke correct?
Please, god please, tell me how what I said helps support my views, go on, Ill paypal you $10 for trying.

No im “shooting down” your quote because it shows absolutely nothing, and adds zero to either side discussion. For us, no, we cant take it as “proof”, but im not using it as “proof”, I posted it to show that garrett believes turbos don’t like operating in surge. Simple.

Because this info is in their FAQ (and also turbo tech section), doesn’t mean crap.
Its not like they go “Oh well, its only a FAQ section, we’re not sure if surge is bad, but it’s a FAQ, so lets just say it is anyways”.
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When turbochargers operate in surge for long periods of time, bearing failures may occur

Please explain to me your interpretations of continuous and continued, and how they relate to Garrett's own words: "long periods of time" (which you so beautifully claimed they did not say).

Ok, my bad. I was reading from garrets turbo tech section, not from the FAQs. There are 2 sections that apply.

1. Surge is the left hand boundary of the compressor map. Operation to the left of this line represents a region of flow instability. This region is characterized by mild flutter to wildly fluctuating boost and “barking” from the compressor. Continued operation within this region can lead to premature turbo failure due to heavy thrust loading.
   
   
2. When turbochargers operate in surge for long periods of time, bearing failures may occur. When referencing a compressor map, the surge line is the line bordering the islands on their far left side.

Either way, what I said still stands:

This could very easily mean - if the turbo continues to see surge conditions throughout its life, this may lead to early failure. NOWHERE in that statement does it imply that the surge needs to be continual for the effects to be damaging, so don’t try and pretend it does, ok.

Garrett says it themselves, CAN cause damage when in CONTINUOUS or LONG PERIODS of time in the surge region.

Infact if you read on slightly, you’ll also come to this statement:

This situation is commonly addressed by using a Blow-Off Valves (BOV) or bypass valve.

Please explain to me your interpretations of continuous and continued, and how they relate to Garrett's own words: "long periods of time" (which you so beautifully claimed they did not say).

I was relating it to the words:

Continued operation within this region can lead to premature turbo failure due to heavy thrust loading.

Continuous – Doesn’t stop.
Continued – Can mean continuous ASWELL as "repeating into the future", Can easily mean either one.

Eitherway, the quote below shows that they are implying continued, short surges, not only a single continuous surge.

This situation is commonly addressed by using a Blow-Off Valves (BOV) or bypass valve.

[Muzz]

10-15 seconds of surge = x ammount of boost pushing back for 10-15 seconds of mayhem.
Off throttle surge = x ammount of boost in a given volume leaking back through the compressor, obviously diminishing pressure quickly over time, thus also force.

I really cant imagine that for the 0.3-0.5 seconds that your foots off the accelerator that that’s enough time for the boost to go below what it is set at.
Think about it, when the throttle snaps shut, there is a massive spike of boost, the turbos still spinning like crazy, but decelerating quickly.
In that .5 seconds max, I really cant see it slowing to the point that boost is actually going to drop back down and below the regular boost setting, with the turbo still spinning at a great rate of knots.

Infact, id put every cent of my money on the AVERAGE boost level for the .5 seconds that the throttle is snapped shut, being well above the stock boost level. I very strongly doubt that the average level of boost for that time to be less then where the boost is set.

You thought you were being smart with your pedanticism over the term "force", you have failed.

You thought you were being smart with your term pedanticism, you have failed. <-god that sounds gay, huh.

Also, explain to my why metal which is already hot "probably" won't have it's temperature affected by friction. I thought you did mechanical engineering???

Im basing that on the fact that a piece of metal at 300 degrease isn’t going to get hotter if 250 degrees of heat is applied, infact the 250 degrease of heat will actually cool the metal at 300 degrease. I’m not to sure what happens with heat energy from friction hence the word “Probably”.
Either way, id say the heat change will be nothing compared to if we were talking about the same friction on cold metal.

I don’t do mechanical engineering, im studying it, big difference. Im only 1.5 years into it, got a hell of a lot to learn yet.

Anyways, arguing about this shit is completly pointless, if you reply, i agree with everything you have to say.
Im over this crap.

[BAMBANG PAMUNGKAS]

bov = great if ur a ricer

[krogoth]

bov = great if ur a ricer

orly? dont all skylines come with stock bovs?

[kazam]

wow, after 10 pages of replies you say sumthing as stupid as BOV = great if ur a ricer?....

[BAMBANG PAMUNGKAS]

serious man. bov are good if they are plumback.

otherwise, wtf they do. nothing but make noise and reduce compressor surge / dose. thats right.

so its a ricer mod.

[string]

Whoa burn; you 'study' mechanical engineering not 'do' it... For a second there I was completely confused! Please, be a bit more pedantic, it makes you sound oh so smart...

Stop trying to pretend that your interpretation of their FAQ is any more correct than mine. Nowhere in the FAQ does it provide any conclusive evidence for either case, so either dig deeper or keep your "proof" to yourself.

Can't wait to get a hold of some Muzz Thrust Bearings. They cool down with friction, but only when they get to operating temperature! Genius!

[Muzz]

Dude, you are to funny, i had to reply.

Whoa burn; you 'study' mechanical engineering not 'do' it... For a second there I was completely confused! Please, be a bit more pedantic, it makes you sound oh so smart...

Dude WTF is wrong with you? Seriously, you state:

Also, explain to my why metal which is already hot "probably" won't have it's temperature affected by friction. I thought you did mechanical engineering???

I took this as "i thought you would know, cus your an engineer"

My reply "i dont know everything, im not an engineer, only a student"

And you come back with this gay shit?

Whoa burn; you 'study' mechanical engineering not 'do' it... For a second there I was completely confused! Please, be a bit more pedantic, it makes you sound oh so smart...

ABSOLUTLY ***ING PATHETIC
Dude i was simply replying to what you said to me.
Shits getting real low when your comeback is at me, for defending my lack of knowledge, against you.

Stop trying to pretend that your interpretation of their FAQ is any more correct than mine. Nowhere in the FAQ does it provide any conclusive evidence for either case, so either dig deeper or keep your "proof" to yourself.

Dude, do you even read what i write?

For us, no, we cant take it as “proof”, but im not using it as “proof”, I posted it to show that garrett believes turbos don’t like operating in surge. Simple.

You sir, are a complete and utter dumbass

My interpretation of garrets FAQ, dumbass, is simply that garrett are stating that surge is bad for the turbo, nothing more.

Well what do you know, in the FAQ garrett is stating that surge is bad.
Im not INTERPRETING shit, im looking at garretts site, and looking at where there stating its bad.

Did i ever say it was proof? NO
Did i say to us, its not proof? YES
Did i say, i cant imagine them stating that without their own proof? YES
Do you keep making more of an ass of yourself? YES
Are you an idiot? DOUBLE YES

Can't wait to get a hold of some Muzz Thrust Bearings. They cool down with friction, but only when they get to operating temperature! Genius!

Dude, go back, READ.
Im not even talking about bearings, im stating fact about heat transfer.
If somthing at 300 deg is in contact with somthing at 250 deg, it will cool down.

OBVIOUSLY this isnt gunna happen, because what the hell is going to cool the bearings down? The point, which obviously flew straight over your head, is that somthings thats hot, isnt going to suffer a massive rise in heat, as its already chocka block full of heat energy already, and is going to absorb heat at a much much slower rate than somthing which is cool.

[Muzz]

Sting, open your eyes, your wasting your time arguing with somone whos not on either side.

Im not for or against BOVs, its all a matter of what you value, both sides of the argument are perfectly valid, and your still here bitching at me for being wrong? Good on ya!

Your doing such a great job as a soldier for the "no bov's" crew, you should be very proud.

How can i be wrong when my opinion is:

To run one, or not to run one, simple question.

Run one if you like the noise or you want your turbo to be working in the best possible conditions, and the extra cost dosnt bother you.

Dont run one, if you dont like the noise, your focoused on weight reduction, are scared of adding somthing else which can malfunction, you like the dose sound, or your happy to risk maby reducing your turbos working life, to save some cash.

Its ALL about what you value in your system

I’m the kind of person that wants every thing working exactly as intended, I would like to know that my turbo is working in the best conditions I can give it. If I can eliminate it from having to deal with it regularly seeing surge conditions for a reasonable price, I will.
I guess you could say, I value long service life mostly, and I do. I want my setup to run like an oem designed system, with everything working exactly as intended.

You seem to be the kind of person that isn’t going to spend his money on a product that he will never really see much of a benefit from. And when it really comes down to it, you aren’t, the downside being that your turbo will be exposed to harsher conditions, which may, or may not effect turbo life. And as I’ve stated, NONE of us have the knowledge to say how much it will.

Your wasting your time, and mine.