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warpspeed
02-11-2004, 05:00 PM
Say guys, can you help me out here. It was somewhere in one of the thread that speaks about a BOV where you can do a 60/40 set up and the Evo doesn't have any problems with idle and you still have that "swooosh" sound. I forgot the name of the BOV. What is the name. I know it cost about $280+

BluEvo
02-11-2004, 05:04 PM
Say guys, can you help me out here. It was somewhere in one of the thread that speaks about a BOV where you can do a 60/40 set up and the Evo doesn't have any problems with idle and you still have that "swooosh" sound. I forgot the name of the BOV. What is the name. I know it cost about $280+
that was the GFB, and it costs about $300. according gb motorsports/mpj performance, they might be able to have some at the meet a little bit cheaper on a group buy.

warpspeed
02-11-2004, 05:10 PM
Cool. Thanks alot for the info. I sure hope that somebody at the meet has one on their Evo so I can check it out. If I like it...well.....there goes my credit card! That is one of the main reasons I wanted the Evo. I like that "swoooosh" sound.

BluEvo
02-11-2004, 05:15 PM
Cool. Thanks alot for the info. I sure hope that somebody at the meet has one on their Evo so I can check it out. If I like it...well.....there goes my credit card! That is one of the main reasons I wanted the Evo. I like that "swoooosh" sound.

you should check out jstockdales Works equiped ride at the meet. thats where i first saw and heard (might i mention drooled) the GFB. it's bad-a$$!

thomas
02-11-2004, 05:49 PM
im glad someone started a BOV thread...anyway...

i got a question for some of y'all: i juss put my greddy type-s bov on and did some driving. noticed that my stock bov holds a lil' higher than that of my greddy. very interesting...

***oh yea, my gauge isnt accurate*** i think i reads 0.5-1.0psi higher than it suppose to...but...

my stock (WOT) hits between 21-22psi and now my greddy shows 20-21psi...whats the deal here? can someone explain to me why my "aftermarket" bov isnt holding/showing accurate numbers? or is it my gauge, that POS, auto-fucking-meter! haha, j/k.

any input would be appreciated, TIA.

and yes, all hoses and clamps are tite. greddy bov "nut" on top is at softest setting, i read somewhere on evoM that that was the way it ought to be. i dunno :roll:

BluEvo
02-11-2004, 06:02 PM
this is what i seen in posts, but i don't recall where. the greddy one leaks (as like other after market bov), even when everthing is tightened down. i used to have the greddy one on my 99 eclipse and it leaked. don't hold me to it though, it's just what i've read out there for the evos. r u running vta or recirc?

EvolvedDSM
02-11-2004, 06:43 PM
I ran a Type-S on my DSMs and played with it for a while until I got it to work at an acceptable level. I even called GReddy about it and they said they didn't recommend running it above 17PSI. The problem is that the spring is too soft to run high boost. You can tighten it, but that limits how far the valve can move and you run into compressor surge issues. I did find a level that finally worked for me, but it was a bit of a compromise since I was hitting 23PSI religiously. I found it helpful to hook up the lower nipple (to any boost source--such as that nipple off the pipe leading from the turbo) and then just adjust in small increments. I also had a friend that took his Type-S apart and replaced the spring inside with something stiffer, but he couldn't provide me with any info about the spring itself.

559EVO
02-11-2004, 08:08 PM
I will be at the meet too and if anyone has GFB/WORKS BOV'S for sale there count me in.

BluEvo
02-11-2004, 08:37 PM
There has been efforts in getting these GFB bov's in the Meets and Events forum under > Parts Poll for meet #3.here is the reply from mpj/gb for the 28th meet >


It is more than likely we will have a bunch of the GFB stealths on hand for you. Pricing is less than amazing due to the recent increase by GFB when they moved to a central US distributor model.

MSRP for the Stealth is now $339, I think on a one to one basis we can offer them at $299. If there is significant interest we would be willing to work on the pricing as much as we can.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com

I guess pm Mike, so he can get list of how many ppl r interested and have them available for hopefully a group buy discount. :)

GReddy_917
02-11-2004, 09:20 PM
I alread emailed the guys to request the BOV...I suggest all intersted do the same.

thomas
02-11-2004, 10:58 PM
thx for the feedback fellas...

looks like ima gonna look for a new BOV! vroooom, pshhhh!!!! :shock:

rite now i do have it recir., i think tomorrow ill put the stocker back on.

POS. that thing sounded awesome on my 1g talon.

jstockdale
02-11-2004, 11:44 PM
Guys, remember that WORKS offers the same part, preset for the Evo, with a 3 year warranty for $299, and the Holiday Special (which I might be able to get us if we have sufficient interest) was $289. They are working directly with GFB Australia to get these things imported and set up for our Evo's. That's where I got mine (but I got a lot of gear earlier than it was fully available) and they should be available to everyone in 1-2 weeks.

No offense to GB/MPJ but WORKS found these valves and is standing behind them at a good price. I think it'd be cool if we bought from WORKS.

:)

-S ...

warpspeed
02-12-2004, 03:07 PM
Would that be $299/$300 OTD?

thomas
02-12-2004, 06:23 PM
no prob, if i decide to buy one. ill go with WORKS. :wink:

i put my stocker back on today. no problems, rite back to where i started, boosting approx. 21-22 psi, depending on the gear. took a couple of minutes for the stock to "settle" down, but once it got acquainted again, it was alllllll graaaaavy. i guess ill be in silent mode until i decide what i want to get.

FS: anybody want to purchase a greddy type-s BOV. haha. now that we all kno it leaks. phucking POS. (___;___)

MPJ Performance
02-12-2004, 10:59 PM
Hi folks, don't mean to sound rude or funny here but nobody found these valves they have been available for some time (we have been a authorized GFB dealer for nearly 3 years now) what's more is that GFB have now switched to a main US distribution network from one sole US distributor and it is a local company but it is neither us nor Works.

The existing importer was MRT from Australia and I believe the still do some importing into the US how long for I do not know.

Whether you buy from us, Works or somewhere else the main thing is you get the right part and at the right price for you. If we can assist you with that great! if we can help you in anyway and you want to purchase somewhere else that is fine too, we're here to help as much as we can.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com

nebolic
02-12-2004, 11:20 PM
Mike,

Thanks for being a gentleman about this situation. As for me, I just need to get my hands on a GFB unit on the feb 28th meet..... whether its from Works or GB Motorsports, they're both great vendors, so we'll just see who has what in stock and what they can offer from there.

Nebo

GReddy_917
02-13-2004, 07:07 AM
He is right you guys, GFB Hybrid valves have been out for at least 3+ years now...I dont see why WORKS should be given the credit for a "find". I was running the Hybrid GFB on my GVR4 almost 4 years ago...its old news really.

JanSolo
02-13-2004, 09:09 AM
It's not about taking credit for a find, but they appear to be the only company that has pushed them for the Evo. They announced them in the December time frame for the Evo and I have never heard anything from any other vendor about them till just recently.

jstockdale
02-13-2004, 11:11 AM
What Jan said. :)

-S ...


It's not about taking credit for a find, but they appear to be the only company that has pushed them for the Evo. They announced them in the December time frame for the Evo and I have never heard anything from any other vendor about them till just recently.

BluEvo
02-13-2004, 11:27 AM
generally speaking, customers are going to buy it from which ever vendor has the correct application available and ready to go for a good price. the purpose of an evo meet at GB/MPJ Performance shop is to promote and support that vendor for that day. while in turn supporting our tuning needs with selected deals and pricing. of course other vendors r welcome to join the event, the more the merrier right?. when u guys were at Vishnu u guys were buying and supporting his products in turn for discounted items (reflashes) and vice versa. i mean it should not turn into a vendor war. everyone will have a favored shop, but we are here to support all our local shops and have fun meeting them and doing good business. i'm sure in the future events and meets, we might plan a Works day and Gruppe-S day etc....as they become available to us. :wink:

MPJ Performance
02-13-2004, 05:22 PM
It would appear that my post may be a little misleading, I was not trying to take away anything from anyone for selling the bov's or finding them so to speak I was just trying to point out that a bov that can be adapted to fit the Evo 8 has been around for a while is all. The reason we have not been offering them is mainly due to the fact that until we saw demand we really did not think anyone would be interested in spending $300 or close to it for a bov, We were wrong! (GFB pricing used to be $259 list then went up to $339)

Something to add is that GFB now have a Stealth FX bov specific to the Evo 8 and they will be available in the US within 2 weeks (unless someone brings them in direct from Aus in the meantime)

We are trying to get some here in time for the BBQ if anyone is interested please let me know.

Mike

(510) 487-4447
www.mpjperformance.com
www.gb-motorsports.com

jstockdale
02-15-2004, 12:08 AM
FYI: There's been some questions regarding the GFB BOV and why I have some degree of backfiring with partial venting. I originally responded to the question via PM with another NorCalEvo member, but after writing it I figured I might as well post it for everyone to reference if interested.

Question: What causes the backfiring? Is it a result of our ECU Flash or the BOV itself?

Well, actually the backfiring isn't really a side effect of the flash. The severity is influenced by the fuel distribution at the shift point (which is in turn related to the fuel maps altered by the flash) but the backfiring itself has to do with the Mass AirFlow sensor. Basically, the car determines the proper Air/Fuel ratio by metering the air that passes into the intake. It then knows that (since the car is meant to operate in a closed state from intake to the engine) there is "supposed" to be X amount of air and administers the fuel appropriately.

Now, as soon as you start VTA in any capacity, the amount of air that the car sees going through the intake is not the same as that which enters the engine (as the vented air breaks the closed operation state) but since the car has no way of knowing that the air was vented, it still administers the same amout of fuel. This results in a temporary run rich condition. Enough of the fuel fails to combust in the chamber and gets spat out the exhaust that the car backfires. Now the backfire is minimized with the GFB valve (since it recircs first and then vents, and is adjustable) and stalling is prevented altogether. So the GFB basically makes the very best of a bad situation.

Without replacing the MAF sensor with another air metering method, there isn't any way to run any signficant amout of air VTA without either backfiring, or stalling.

-S ...

*** EDIT ***
If anything the flash will reduce the amount of backfiring (but the change might not be noticable) due to the leaner air/fuel ratio used on both the Xflash and Brain Flash.
*** END ***

nebolic
02-15-2004, 12:39 AM
thanks J

thats been one of the more useful techinical posts thus far on NorcalEvo. It also answers a lot of questions.

06IXMR
10-18-2006, 08:46 PM
Bravo :D

evo_dadi
10-18-2006, 10:20 PM
holy back from the dead!! :P :lol:

YldEvoMr06
10-29-2006, 07:53 PM
A boost controller is a valve, either passive or active, that regulates the flow of pressure to the wastegate actuator of a turbocharger.A turbo charger is a natural feedback device.Exhaust gas drives the turbo, which makes more boost, which causes the engine to make more exhaust gas, which make more boost and so on.Without some kind of moderating influence, the turbo would quickly blow up the engine.
The boost controller sits in the vacuum circuit that goes to the wastegate actuator.The wastegate is a bypass for the turbine (hot) side of the turbo.Allowing exhaust gas to flow out the wastegate prevents the turbo from spinning too fast.The wastegate actuator is a pressure-operated diaphragm that moves the flapper door of the wastegate; as boost pressure increases, that pressure also builds against the wastegate actuator.When the pressure gets to a certain level, the wastegate door opens, and pressure will equalize at the desired maximum.
Most modern cars, including the Lancer Evolution, have a built-in boost control solenoid of some sort.This solenoid allows the engine control unit (ECU) to adjust boost pressure during regular use, or to drastically reduce it in the case of a perceived emergency.(If you filled the car with super-low-octane gas, the ECU might reduce the boost to a minimum, for example.)
An aftermarket boost controller allows independent control of the amount of pressure that reaches the intake manifold, and increased boost (to a point) is great for making more power!Normally, the aftermarket boost control device will take the place of the factory boost control solenoid.This does remove those built in safety features, but it also unlocks the potential for big increases in horsepower.
Aftermarket boost control devices come in mechanical and electronic varieties.The mechanical ones are cheaper and simpler.The electronic ones are more expensive and have more features.
Mechanical boost controllers are usually a fairly simple ball-and-spring valve.They typically are installed under the hood, close to the turbocharger to minimize hose length.They are adjusted by turning a knob that changes the pre-load on the spring.They are easy to install, inexpensive, and simple to use.On the other hand, they can be somewhat inconvenient to adjust.If you want to achieve a desired boost pressure, most inexpensive mechanical controllers require a drive-adjust-repeat method to get to the exact boost level you want.Because of this inconvenience, we find them best for the car owner who wants to set the boost once and then forget about it.
There are a couple exceptions to the general statement about inconvenience, though. The Hallman Evolution boost controller is a traditional mechanical valve with an added cable that extends into the cockpit.The cable can be twisted inside the cockpit, and it adjusts the mechanical controller under the hood.Cost and installation are a little bit higher than the simple traditional mechanical controller, but its still far cheaper than any electronic controller, and is just as convenient.
The TurboXS Dual Stage Boost Controller uses two mechanical valves stuck together with an electric solenoid that switches between them, so although its basically a mechanical valve, you get to choose between two different boost settings from inside the car.
Electronic boost controllers use a solenoid valve instead of a ball and spring, and the electric operation means the mechanical controller can be operated from inside the car.They are more expensive and significantly more work to install, but they are also much more convenient than most mechanical controllers, and they have features no mechanical controller could boast of.Most electronic controllers have at least two boost settings you can switch between, and some have four or more settings.Even the simplest allow real-time adjustment to the boost, so you can change boost levels while you are driving, as often as you wish.The more sophisticated controllers add features like large graphic displays, boost gauge functions, data recording, and more.
Theres no blanket rule about which kind controller is better.The electronic boost control manufacturers claim that the turbocharger will spool faster with an electronic controller, because it can keep the wastegate completely closed until the very last moment.We have not found this to be the case, at least to the point that we can perceive it.Mechanical controllers seem to spool up the turbo just as quickly.

Electronic controllers are popular with people who like to adjust boost frequently.That includes many racers, tinkerers, and general gadget lovers.Some people take advantage of the electronic controllers built in boost gauge features to avoid installing another boost gauge.If price is no object, an electronic controller gives you all the control of a mechanical controller, plus many more features.Our experience, though, is that the electronic solenoids can eventually fail, probably because of contamination from oil or other fluids.The most sophisticated controllers are so complex that it can be difficult to operate them without a few thorough read-throughs of the owners manual.
Mechanical controllers are far more popular than electronic ones, mostly due to the low price.They also are nearly bullet-proof in terms of reliability and longevity.The best of them can be adjusted without tools, and cannot come apart.The cheapest usually need a wrench to loosen a lock nut before adjusting, and they can potentially vibrate apart if the lock nut is not secured.But hey, if your $49 boost controller comes apart, you can afford to buy another.

Having a boost controller can be a great way to add cheap power to your car.Most turbo cars have some headroom built-in, so you can raise the boost some without any damaging effects.But on any car, if you increase the boost too far, the in-cylinder mixture can detonate, causing severe damage to your motor.The horsepower effect of additional boost can be intoxicating!The lure of cranking that boost controller just a little more isirresistible to some of our customers, and those people usually find themselves in need of a new motor.
To understand how much boost the motor can take, read up on the discussion forums.Find out how much boost other people have run on the type of car you have, and find out what modifications they are using.Fuel delivery is the most frequent upgrade needed to increase boost, but the octane level of the gas can also be a limiting factor.The Lancer Evolution runs an incredible 19.5 psi of boost right from the get-go.You will not be able to increase the boost far above that point without somehow increasing the effective octane of the fuel.Additional intercooling, larger turbos (which heat the air less as they compress it), and injection of water or propane into the cylinder can all increase the safe level of boost.
Use diagnostic gauges to help you figure out if you are near the danger zone.A boost gauge is a must if you have a boost controller.An exhaust gas temperature (EGT) guage (also called a pyrometer) is very helpful for understanding in-cylinder conditions.An air/fuel meter is somewhat helpful, although it is not very accurate at full-throttle conditions.Also use your ears and the seat of your pants.A sudden change in exhaust note or relative loss of power at full throttle can mean the engine is retarding spark timing in a response to dangerous detonation.

mtsevovii
10-29-2006, 08:02 PM
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BigEd925
10-29-2006, 08:11 PM
^
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+1,254,325.0005

YldEvoMr06
10-29-2006, 09:14 PM
A compressor bypass valve (CBV) is a vacuum-actuated valve designed to release pressure from the intake tract of a turbo car when the throttle closes.It re-circulates the air back into the intake before the turbo inlet, but after the airflow sensor.
A blow-off valve (BOV) does the same thing, but the released air is vented into the atmosphere.
Purpose of a CBV:
The reason most turbo cars have a CBV is that when the throttle closes and the intake system is under pressure, the high-pressure air entering the motor will bump into the closed throttle plate, and (in the absence of a CBV) a pressure wave will travel back to the turbocharger.The result is that the compressor wheel will stall (a phenomenon known as compressor surge and slow down very quickly.This is hard on the bearings and decreases the turbo's lifespan, but it also means the turbo will take longer to spin up the next time the throttle is opened.
With the CBV in place, the pressurized air in front of the throttle body is released, and the turbo can freewheel happily.When the throttle opens again, the turbo will have a head start and will get up to speed faster, since it never stopped spinning in the first place.
Blow-Off Valves: Pros and Cons
A BOV does the exact same thing as a CBV, but the vented air is released to the atmosphere, causing a loud PSSSSHT!Eventing noise that is distinctive and attention-getting.Many turbo car owners (and people who wish they had turbo cars) love the noise.
The downside of releasing the air to atmosphere is that it has already been metered by the mass air sensor (MAS), and when it blows off the ECU will be injecting the wrong amount of fuel into the cylinders.(The MAS reads ten air units, say, and the ECU tells the injectors to squirt the right amount of fuel for ten air units.But then five of those air units are vented off to atmosphere, and only five make it to the cylinders, and five more have to be drawn from the outside air, through the MAS again) so the engine temporarily runs extremely rich, meaning too much fuel is injected into the cylinders.
This temporary rich condition isn't usually that harmful, but it can cause bucking or hesitation on lift-throttle.If the condition is really bad it can eventually foul spark plugs and even clog the catalytic converter.(Unburned fuel on the cat burns very hot, and too much of it can melt the cat).
You can't vent a stock CBV to atmosphere because the spring setting is too soft, and at idle or part-throttle it will open, which will confuse the MAS and cause rough running, stumbling, and stalling.A stiffer valve (like most aftermarket valves) will stay mostly closed at light vacuum, promoting better behavior when the valve is vented.The downside of stiffer valve spring pressure is that the valve may not open when releasing the throttle from light boost.This can cause some compressor surge (it sounds like a fluttering air noise), and can hinder turbo spool when shifting at light throttle angles.
CBV/BOV Tuning
Adjustable valves have a provision for changing the spring tension of the valve, usually in the form of a screw or a stack of shims for changing the spring preload.Customers often ask us how to set these.The short answer is that you want the valve as softly sprung as possible, while still stiff enough to hold the boost pressure you want to make.If set too soft, the valve will not close correctly the car will idle badly and bog when the throttle closes.If the valve is set too stiff, you will see lots of compressor surge, and the valve will not open at anything less than full pressure, and it will close too early, which defeats the whole purpose of having the valve.Use your boost gauge and your ear to figure out exactly what spring tension your car likes.Another handy tool is a hand vacuum/pressure pump, which you can apply to your stock valve and your aftermarket one to compare their behavior.Start with a spring tension that makes your aftermarket valve behave roughly the way your stock one does, and adjust from there.
BOV Maintenance Notes
We field a steady trickle of tech questions about jamming or sticking BOVs. The nature of a BOV means it is exposed the elements under the hood, and that means sand, grit, road dust, and other debris can get trapped in the works of the valve.Most aftermarket valves can be disassembled and cleaned.If your valve is jamming or doesn't seem to be working right, carefully take it apart, caution, the spring pressure is pretty strong! Eand clean all the parts.Lubricate the valve with whatever substance the manufacturer recommends, and reassemble.We find this solves 90% of all BOV problems.Some BOV's, like the Blitz model, come with an optional filter specifically for preventing this type of problem.
Our Recommendation
The best choice for drivability on the Evo is a CBV, which returns the vented air back to the intake.The stock valve works pretty well, although its plastic construction means it may leak a little at high boost levels.If you are going to run higher-than stock boost, you may want to run an aftermarket valve with tighter and/or adjustable spring pressure.
If you really want the noise and attention of a BOV, go for an aftermarket unit.Be prepared for some occasional stumbling and part-throttle compressor surge, but it's nothing most people can't live with.For a lot of our customers, the sheer thrill of that noise every time they get off the gas is worth any minor issues.

mtsevovii
10-29-2006, 09:16 PM
go home...

BigEd925
10-29-2006, 09:40 PM
where are you quoting these from? you need to give them proper reference.

06IXMR
10-29-2006, 10:24 PM
^ Thats what I was thinking...Great you can read it off a sight and C and P but, wheres the refrence link?

YldEvoMr06
10-29-2006, 10:32 PM
I can't recall where I got that... it's on my archives list... unfortunately i'm just interested with the gist of the subject matter. i'm just sharing it with you guys..

lncrevoviii
10-30-2006, 01:09 AM
:lol: Plagerism, oooooooh.

MR_06
10-31-2006, 12:58 AM
sorry... i couldnt even read any of that... just gave me a headache/eyesore..

mtsevovii
10-31-2006, 09:28 AM
http://i2.tinypic.com/or73no.jpg

they're grreeaaat!!

dabaysevo
10-31-2006, 09:49 AM
This is Jay's fault for bring this thread back from the dead.:D* *^Ouch my eyes, did Peter Parker forget to wash his hero outfit again and was forced to kill Tigger and wear him?

06IXMR
11-01-2006, 02:00 AM
Good its not me. >.> jajaja... yes it is jajaja no hahah.

lncrevoviii
11-01-2006, 07:09 PM
Good its not me. >.> jajaja... yes it is jajaja no hahah.


thats hella beaner...

06IXMR
11-02-2006, 01:09 AM
Good its not me. >.> jajaja... yes it is jajaja no hahah.


thats hella beaner...


Your the beaner!