Wastegates have a totally different purpose than a BOV.

 

if Greddy didn't think BOV's were important.. why on God's earth would they manufacture BOV's... and even sell BOV flanges for their turbo kits

 

Saying "I dont have a BOV and dont currently have issues" is like saying "I do heroin and Im alive whats wrong with it?" Its that fawking stupid.

 

hahaha....that was good

but yeah, i just dont get why you wouldnt want one. I mean, you know what it does, you know what happens if you dont have one, whether or not you are or arent having problems with it for now. So instead of trying to argue that you are fine without one, you gotta admit that its smart to have one

 

Accoring to Beer, it's only to appease the rice culture.

 

Derek the use of a BOV or Diverter valve or Bypass valve helps relive the pressure that builds up on the intake system. The turbocharger keeps spinning even after you let off the gas so this excessive pressure can cause the turbne to sieze which may destroy the turbo unit. Otherwise there is no way to relive this pressure buildup after the throttle plate closes so this is where the BOV will release the pressure to the atmosphere.

 

https://my350z.com/forum/brakes-and-suspension/257157-lowering-the-rear-only-thoughts-comments.html

 

Some turbos are made to spinbackwards, and require no BOV.

 

Working for Ford, Chevy, and/or Dodge actually gives you less credibility.

We're not talking about diesels.

 

I full understand what they do, and the advantages of having a BOV, or better yet a BPV, yet all the talk of why you should have one isn't followed up with proof that you really need one.

No offense meant to the people who have a turbo, but I'd trust a manufacturer over a few people on the internet. And I know that "manufacturer is out to make a buck" but so is the tuner who says you need one and the store that wants to sell it to you.


Like I said some turbines may be built to a price point and not to function, and in many cases may require something to make sure that their bearings don't get worked and some failure happens...but on the GReddy the turbos are built correctly and they use floating bushings.


We can argue all day of this theory of why you need one, and what advantages it has, but I'd like to see some data, which would be proof of failure...little bit of boost response is a performance gain, not a requirement.

AND I say this because when I ask about BOVs, I'm told I don't need one, but if I want one I could buy it.

 

So if you put a turbo on your car and keep the stock exhaust, just because someone tells you that a larger diameter exhaust will provide gains, would you believe them?

 

You're confusing things that add power and are necessary. Your stock exhaust won't cause failure.

Since people like to quote websites here's an interesting read. And like I said, I understand what they do, but they are not needed as much as everybody wants to think

http://www.gofastbits.com.au/index.p...tion=tech_info

Quote from the end of the article...

The interesting thing about compressor surge is that it occurs much more readily at low turbo shaft speeds. At these low shaft speeds, on road cars this is generally between 2000 and 3000 RPM, compressor surge is not much of a problem, as the loads generated by the surge are miniscule compared to what the turbo encounters at high boost. However, if surge occurs at high RPM and boost, it is possible to reduce the turbo life and/or damage the compressor.

 

A BPV is not better than a BOV!! You are uneducated, and simply going off of what your friend told you. In certain cars a BOV is fine, in others (like STI's, EVO's, any VW 1.8T) the BPV is the best option. I wouldnt call either one superior or inferior to the other, in fact most BOV's can be run with recirculation essentially making it a BPV, so what does that do to your BPV > BOV thinking? Make sure to get back to us when you need to get your turbo rebuilt due to compressor surge thanks...

 

The same goes with how can they prove to us that a BOV is worthless or not needed I want tech data on how they came up with this idea. So if a BOV is not needed how would the excessive pressure bleed off when the throttle plate closes??

 

Ok, so there you go Beer Goggles, You just fished your own losing battle.

Guess when you are usually shifting? AT HIGH RPM AND BOOST.

When does a BOV come into play? WHILE SHIFTING, DURING HIGH RPM AND BOOST.

Will a BOV prevent compressor surge? YES.

Will this effectively lengthen the life your turbos? YES.

Will my (and everyone elses) turbos last longer than yours? YES.

Are you a goddamn idiot? YES.

 

Done, done and done.

 

I wish I could my post from a few weeks ago about BPV vs BOV. A Bypass Valve and a Blow Off Valve are the EXACT SAME THING. It can also be called a diverter valve. A Bypass/Blow Off/Diverter Valve all have the exact same function. To remove compressed air from the intake pipe when the throttle plate closes. In the end this is JUST A VALVE TO REMOVE CHARGE AIR. People have called it all kinds of things. Technically I have a Bypass Valve venting to atmosphrere. I also technically have a Blow Off valve venting to atmosphere. There are all words describing the exact same part. How they vent is what determines how effective or detrimental they are. In a car in which the valve is positioned before the MAF sensor you are able to vent the valve discharge to atmosphere with no negative effect. This is because the MAF sensor has not yet metered the air and therefore has not applied fuel to compensate for that air. Re-circulating that air has no benefit as it will be returned in front of the compressor and will need to be compressed again. In a car in which the valve is positioned after the MAF sensor the valve should always be re-circulated as the sensor has already metered this air and applied a correction of fuel for it. In this case the air is routed back in front of the compressor to prevent surging but still keep the air after sensor so it is not metered again. In either case the performance gains are EXACTLY THE SAME. Running a valve to remove the air upon throttle close has a two fold effect. First it prevents the air from attempting to return back into the compressor outlet which cause turbulance and and reversing effect on the compressor (aka compressor surge). This prevents damage to the turbocharger rotating assembly from a force acting on it to reverse its direction at 10, 15, 20, or even 50,000 RPMs. The second benefit is a result of the first. When surge occurs as stated the air is attempting to enter back into the compressor outlet which is acting as a force upon the compressor to reverse its flow. This essentially reduces the momentum of the compressor wheel. Of course the air in the charge pipe is not sufficient to actually halt or reverse the direction of the compressor wheel. It would snap the shaft if it was. However this force acting to reverse the compressor wheel direction will slow the speed of the compressor wheel as it occurs. What does this mean. Well if you were at full boost and your compressor was creating 9 PSI of boost at 56,000 RPMs and you close the throttle to shift without a valve like this the surge would act on the compressor and reduce its shaft speed to lets say 52,000 RPMs (this is purely an example and in no way correct numbers) when you do this the turbo is now producing less air then it was before you closed the throttle. If you were slowing the car down no big deal. But if you are just executing a gear change ideally you want your turbo to maintain its shaft speed so that when you open the throttle again it is immediately producing just as much air as it was before. By having the reversion of air removed somewhere else this doesn't occur and on some minute level would actually improve your turbocharger performance on the transition between gears. Until now I could never tell someone how you would measure that. But now you can:


http://www.autoblog.com/2006/11/03/s...data-recorder/

If you want to be scientific about this run your car with no valve on the intake tract. Monitor and log your shaft speed. Then install a valve and vent it as appropriate for your configuration and perform the same data collection. This will give you empirical proof of whether or not having a bypass\blow off\diverter valve has any positive effect on your turbocharger.

 

not necessary.. i like good lengthy discussions that dont' have personal attacks

 

Read the article.

You guys are retarded. It's like speaking with children.


Like I said show me some failure or wear that was attributed to the lack of BOV/BPV and you can argue, until then all you can do is be a kid.

Anybody just read Jim Wolf's TK having a recirc and the only reason they went atmospheric is to please people who want that sound?

But attack away, throw out, that you turbo may last longer than mine, and continue to ignore counterpoints and argue with me like women.

I, unlike some of you, not all, can understand both sides of a discussion.

 

I'll repeat myself again, I understand the advantage of having one, but it's NOT so much an issue with surge effecting the turbo, it's a performance gain. It's just not going to have that much of an affect as people want to say.

And again, I'll believe a "friend" who does this stuff for a living over 90% of the people on the internet. And you can use that logic with me too.