[swedeseed850]

vw's are for loosers
no one that has a vw is an individualist
they all follow the crowd and listen to lil wayne

oh, really. Well, I have a 69 beetle with a 911 porshe motor. I like lil wayne, my bug is as individualized as it gets, and it never follows, only haters do. I love my volvo, more than any car Ive ever owned, but the bug is fun for pink slip snatching.

[swedeseed850]

the closer to the throttle body the better. how'd you manage to build up "enough ponies" without knowing where to put a blowoff valve?

LOL , really on the dyno it didnt make a differnce. Just it was stronger on the metal piping. 400 and gaining.

[nolanator]

LOL , really on the dyno it didnt make a differnce. Just it was stronger on the metal piping. 400 and gaining.

what do you mean it didn't make a difference on the dyno? what do you think a blowoff valve does? btw you should post pics in the showroom

[swedeseed850]

what do you mean it didn't make a difference on the dyno? what do you think a blow-off valve does? btw you should post pics in the showroom

Done. check em out. Well, I have a dyno at the shop. I NEVER install or tune without confirmation of its works toward the performance of my Vo. Plus, the in car dyno, that i respectively programed myself, allows real time tuning or most all variables. Really, the position of the BOV was in the fresh air line, via turbo to intercooler as a test to see how the vo would respond to that position, but since i make all my own turbo piping custom, it has been moved to the I.C to throttle body pipe. The issue was brought up by a fellow S70 owner that claimed I was moving it for no reason, I knew where it belonged, but we wanted to see the spike curve difference, as there were none. Funny, of all the volvo forums out here, this one seems the most opinionated, arrogant forums ive come across. You should make people feel welcome, not like idiots. I know the true 'volvospeed', the site forerunner, he never seemed so pompous. But im sure you will be just as opinionated over my garage pics too, but I have a tendency to build to stand out. Thanks for your opinion, but they are like a**holes, everybody has them. Volvo-4-life.

[EricF]

Done. check em out. Well, I have a dyno at the shop. I NEVER install or tune without confirmation of its works toward the performance of my Vo. Plus, the in car dyno, that i respectively programed myself, allows real time tuning or most all variables. Really, the position of the BOV was in the fresh air line, via turbo to intercooler as a test to see how the vo would respond to that position, but since i make all my own turbo piping custom, it has been moved to the I.C to throttle body pipe. The issue was brought up by a fellow S70 owner that claimed I was moving it for no reason, I knew where it belonged, but we wanted to see the spike curve difference, as there were none. Funny, of all the volvo forums out here, this one seems the most opinionated, arrogant forums ive come across. You should make people feel welcome, not like idiots. I know the true 'volvospeed', the site forerunner, he never seemed so pompous. But im sure you will be just as opinionated over my garage pics too, but I have a tendency to build to stand out. Thanks for your opinion, but they are like a**holes, everybody has them. Volvo-4-life.

You are correct, it's not a big difference either way. It doesn't "belong" one place or another either

Johann once posted the idea that if you vent pre-intercooler, the blowoff valve lets off air that has not been cooled yet. That is logical to me.. I have mine after the intercooler, but there's nothing wrong with before it and it might even make more sense.

To each his own, I think it's a silly argument. That's why I made this sticky post. I was tired to see even more asinine aspects of installing a BOV being discussed/argued about on here with new discussions/threads being started every day about the same damned thing. Thought should be devoted towards sizing turbos, finding tuning solutions, intercooler possibilities, etc It's a pity for people to spend so much time/effort dwelling on the little stuff. It's even sadder for people to bring negative attitudes to discussions about silly little things.

My 'attitude' in the first post was just expressing my frustration about how insistent people are about arguing over blowoff valves

[ozzimark]

what do you mean it didn't make a difference on the dyno? what do you think a blowoff valve does? btw you should post pics in the showroom

If operating properly, the location of the BOV doesn't mean stuff when you're on the throttle. It's closed. It only matters when you let off the throttle, which is behavior that a dyno doesn't record.
Instead of arguing where you should put your bypass valves, instead argue how much air you should be flowing out of it. The turbo cares about that, and it actually makes a difference when you get back on the throttle

And Eric, it's ok, you can tell us how you really feel about BOVs

[supra_stephe]

You guys are so cute about this.

The CBV is located in a bad spot. A recirculation valve (the actual name for BOV's) dose the same thing, right back into the intake system. Back in the day when only the cool kids had BOV it was due to recalculating pressurized air would back up and because a surge. Messing up your turbo : ( . Also at this time the only kids rocking them had lots-o-boost and lots-o-power. Then DSM kids discovered how to make the stock 1g recirculation valve make the mad tite JDM sounds like racecars! Then they discovered how leak valves worked and smashed the top so they open later (under more pressure). and thus the BOV.

If you are worried about surge I'd get a surge valve, it works like a BOV but only opens (and stays open) under surge. You just set it higher then your boost level and when you get compressor surge it pops open.




Side note: wheels are tires are a performance mod, but not if they are PEGS that are super heavy and not wide.

[nolanator]

You guys are so cute about this.

The CBV is located in a bad spot. A recirculation valve (the actual name for BOV's) dose the same thing, right back into the intake system. Back in the day when only the cool kids had BOV it was due to recalculating pressurized air would back up and because a surge. Messing up your turbo : ( . Also at this time the only kids rocking them had lots-o-boost and lots-o-power. Then DSM kids discovered how to make the stock 1g recirculation valve make the mad tite JDM sounds like racecars! Then they discovered how leak valves worked and smashed the top so they open later (under more pressure). and thus the BOV.

If you are worried about surge I'd get a surge valve, it works like a BOV but only opens (and stays open) under surge. You just set it higher then your boost level and when you get compressor surge it pops open.




Side note: wheels are tires are a performance mod, but not if they are PEGS that are super heavy and not wide.

speaking of cute...you spell "does" funny

[Dave 54]

If you are running higher than stock boost levels than you may want to look into a CBV rebuild kit from Quickbricks.com. The original stock diaphram most likely won't be able to withstand the raised boost level due to age(worn out). This kit comes with a new diaphram and 5 shims to allow a 20 psi set up. I purchased this because mine was leaking at 19psi and all I can say is that it does what is said, and install is very simple.

[Caine]

to continue answering the question that was originally asked...

The richness cause as a result of the loss of metered air will result in some carbon build up in you exhaust system due to combustion occurring there. The likelihood of methodical damage to your CAT is also negligible (opinion only) because this occurs under low pressures and doesn't generate the kind of temperatures that combustion chambers create (compressed combustion). Your CAT is exposed to much higher temperatures based on spirited driving EGTs alone.

On an application such as a Volvo, nice as they are, they don't usually make GOBS of power, and thus, a BOV isn't necessarily more useful than a BPV. They are, for this application, pretty noises for you to listen to.

In a different application, like a 2006 Subaru STI, a BOV can provide a much needed RAPID venting off of pressure. I was having a problem with over-revving on up-shifts when my boost was not lowering fast enough THROUGH the BPV. I would lift at 6900rpm and RPM would jump to 7300(then immediately die down) due to the pressure not venting rapidly enough. After installation of a hybrid (~50/50 recirc/vent) valve, my boost declines rapidly upon lifting and I do not overrev on shifts any longer.

This adds HP to my car in that my car will continue to work in the future!!! When broken HP = 0. When operating HP = 350. My hybrid BOV nets me 350HP by keeping my car from eating itself!

[Naughty33W]

a cbv vents back into the intake system , and a bov vents to atmosphere ... wouldnt the cbv be vented preheated air back into your intake system ? or is it just a negligible amount ?

[S70speed1717]

Caine, on 19 April 2009 - 08:54 PM, said:

to continue answering the question that was originally asked...

The richness cause as a result of the loss of metered air will result in some carbon build up in you exhaust system due to combustion occurring there. The likelihood of methodical damage to your CAT is also negligible (opinion only) because this occurs under low pressures and doesn't generate the kind of temperatures that combustion chambers create (compressed combustion). Your CAT is exposed to much higher temperatures based on spirited driving EGTs alone.

On an application such as a Volvo, nice as they are, they don't usually make GOBS of power, and thus, a BOV isn't necessarily more useful than a BPV. They are, for this application, pretty noises for you to listen to.

In a different application, like a 2006 Subaru STI, a BOV can provide a much needed RAPID venting off of pressure. I was having a problem with over-revving on up-shifts when my boost was not lowering fast enough THROUGH the BPV. I would lift at 6900rpm and RPM would jump to 7300(then immediately die down) due to the pressure not venting rapidly enough. After installation of a hybrid (~50/50 recirc/vent) valve, my boost declines rapidly upon lifting and I do not overrev on shifts any longer.

This adds HP to my car in that my car will continue to work in the future!!! When broken HP = 0. When operating HP = 350. My hybrid BOV nets me 350HP by keeping my car from eating itself!

I have a 99 Volvo S70 glt with the lpt 13G turbo.
I have intake and exhaust and an st stage 2 tune. I plated off my cbv, and added a turbo xs bov. When I first installed it when I let off the throttle my car would die. I shimmed it up, and now it doesn't die, but it has turbo flutter at the lower boost settings....and everytime it blows off it fills the cabin with a horrible exhaust smell.
Any tips or ideas?

[mrbrightside2009]

i put a cone filter on my stock hose and it sounds like a blowoff valve lol when u let go of the gas. good enough for me.

[Boogs]

Just to be clear, a BOV doesn't add performance! A BOV is designed to help keep the turbo spooled and reduce stress between shifts when the throttle plate is closed. When the throttle is closed the compressed and metered air comes to a temporary halt which ends up pressurizing the piping which slows the compressor down until the throttle plate is opened again. In engines that have MAF systems like ours the metered air isn't routed to the atmosphere but rather piped back into the system. Think of it as air that has been accounted for. This prevents a rich condition as the ecu has already altered the duty cycle of the injectors to add more fuel. This is why you see MAF cars with atmospheric BOVs puffing black smoke between shifts or see a sooty residue on their bumpers above the exhaust.

A BOV ideally should be mounted close to the turbo where it can vent the pressurized air before it reaches the compressor. Look at any Pro drag car that's turbocharged and if it's done right they are running one or two BOVs close to the turbos 6-12". So BOVs aren't stupid on auto tranny car because it's serving a function. Just ask the sub 8-second 1200hp turbo cars that use powerglides if they are stupid.

[TyConn_S70]

god I just farted so hard

[SilverS60R]

http://www.youtube.c...h?v=ZxFFJQZOEiY

I thought this would be interesting to add in there. People claim that the BOV doesnt add performance. The link above is on a MS3 they just switch out the stock BOV for an Aftermarket. I know its not CBV to BOV but I thought this was an interesting Video.

[KoolAidKid]

SilverS60R, on 07 October 2009 - 11:41 AM, said:

http://www.youtube.c...h?v=ZxFFJQZOEiY

I thought this would be interesting to add in there. People claim that the BOV doesnt add performance. The link above is on a MS3 they just switch out the stock BOV for an Aftermarket. I know its not CBV to BOV but I thought this was an interesting Video.

So he had a boost leak they fixed it and the car made more power? HOLY SHIT! CANIHAZ2PLEEZ?

[SilverS60R]

KoolAidKid, on 07 October 2009 - 10:31 AM, said:

So he had a boost leak they fixed it and the car made more power? HOLY stuff! CANIHAZ2PLEEZ?

Yeah a boost leak, fixed and pushing more power than stock when it isnt leaking LOL