blow off valves

speedmo21

Member
hey whats up.ive got a turboxs boost controller..ive got it set around 9psi..im lookin into bovs and really want the turboxs RFL bov...however it says for use w/cars pushin 10-25psi...should i still get the rfl..or any other suggestions of a nice soundin bov
 
Apex-i makes an awesome "dual chamber" bov. It sounds pretty cool, I'm not sure about $$ though. Im pretty sure it will handle most any boost because of the dual chamber. Its on their site www.Apexi.com
 
new to this

I have a few questions about the mazdaspeed 03 protege...i have one and was wondering how i get the turbo to sound like it is blowing off air when i shift...i have heard of a blow off valve and was told that this is what it takes to make that happen but i was wondering what kind of applications i need to make that happen...i also wanted to put a sports exhaust on my car and was wondering if i could jus buy a muffler tip or do i have to pipe out the whole exhaust...i heard that if u dont pipe the whole exhaust out your muffler sounds like a lawn mower...lol...can anyone help me with these problems it will be greatly appreciated
 
hey man. welcome to the forums. check out all the subforums...they will be incredibly helpful in answering those questions and many more. just for starters, if u want the nice blow off sound u need to buy a bov. some ppl run with just a bov, others use a dual setup (bov and bpv) to eliminate stalling issues. there are many different options. also for the exhaust, striker has 2 great threads (one being for exhaust sound clips and the other explaining the entire exhaust system).

search search search
 
mspHtown said:
hey man. welcome to the forums. check out all the subforums...they will be incredibly helpful in answering those questions and many more. just for starters, if u want the nice blow off sound u need to buy a bov. some ppl run with just a bov, others use a dual setup (bov and bpv) to eliminate stalling issues. there are many different options. also for the exhaust, striker has 2 great threads (one being for exhaust sound clips and the other explaining the entire exhaust system).

search search search

Hey, first thanx for the love, people can be real ass' when u jus ask a question around here...so u are saying that all i need is a bov? Some other guy told me that too and he also mentioned stalling but didnt mention a bpv. What exactly is a bpv? And with my stock exhaust on my msp can i just buy a sound clip and get a decent sound?
 
first thing's first. it sounds like you don't really understand how a turbocharger system works. www.howstuffworks.com has a writeup if i recall correctly. read that first :).

ok now that you've read that, here's the reason for using a blow off valve. when the throttle is open and the turbo is compressing air, everything's great. now when you take your foot off of the accelerator and close the throttle plate, all that compressed air slams up against it and has nowhere to go except backwards. it ends up flowing backwards into the compressor....which is spinning at probably 20k-30k and upwards (some turbines spin at 100k and higher). doesn't sound like a pretty picture huh? the compressor will be forced to slow down severely, making spool-up time between shifts longer and can damage the compressor over time.

a bov is basically a controlled leak in your turbocharger system. when the throttle plate is open, the bov stays closed. when you close the plate though, a valve inside the bov opens to release the excess pressure in the system and prevent all that compressed air from back-flowing into the compressor. if you want to see diagrams of actual bovs, go here: www.blowoffvalves.com.

a bypass valve (bpv) is basically a bov. the difference is that instead of releasing all that air into the atmosphere, it sends it back into the intake tract, BEFORE the comrpessor but AFTER the mass air flow sensor (maf). many maf-equipped cars use this because it prevents them from stalling out. many race cars use this because it aids in faster spool-up time between shifts. if you really wanna know the whole business behind all this stalling stuff, pm me and i'll help ya out :).

the msp is already equipped with a bpv....that's what causes the so-called "turkey" sound our cars are known for. you can see it quite easily if you pop the hood. trace your turbocharger piping and you'll see a hose coming off of the turbo-to-intercooler pipe that leads to a small circular looking thing (that's the bpv) and another hose which leads from the bpv to the intake piping. now something really interesting happens when you add an intake...that turkey gets freakin loud! search around the forums, there's a couple soundclips of it.

now you mentioned you were looking for a sound like a quick release of air....like a pssssht sound. www.blowoffvalves.com has soundclips of a bunch of bovs. but if you're looking for a straight air sound with no bells or whistles, a couple ones to consider would be: blitz dual drive, apexi bov, tial bov (i think it's called the raptor), any turboxs bov, hks super sequential (provided you go with the purple insert). you may also want to look into the bov kit made by forge motorsports. it's specific to our car....search the forums for more info. i'm not sure how the greddy rs sounds....never heard one before.

certain bovs can produce a whistling type sound if you're into that. if you ever watched fast & the furious (don't lie, we all did), that whistling sound the green eclipse makes....that's a greddy type-s bov. the hks ssqv makes a similar but very distinct sound.

hope that answers most of your questions.
 
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03mazdashawty said:
Hey, first thanx for the love, people can be real ass' when u jus ask a question around here...so u are saying that all i need is a bov? Some other guy told me that too and he also mentioned stalling but didnt mention a bpv. What exactly is a bpv? And with my stock exhaust on my msp can i just buy a sound clip and get a decent sound?

Yeah I told you and you didn't even take my advice.
 
Striker187 said:
first thing's first. it sounds like you don't really understand how a turbocharger system works. www.howstuffworks.com has a writeup if i recall correctly. read that first :).

ok now that you've read that, here's the reason for using a blow off valve. when the throttle is open and the turbo is compressing air, everything's great. now when you take your foot off of the accelerator and close the throttle plate, all that compressed air slams up against and has nowhere to go except backwards. it ends up flowing backwards into the compressor....which is spinning at probably 20k-30k and upwards (some turbines spin at 100k and higher). doesn't sound like a pretty picture huh? the compressor will be forced to slow down severely, making spool-up time between shifts longer and can damage the compressor over time.

a bov is basically a controlled leak in your turbocharger system. when the throttle plate is open, the bov stays closed. when you close the plate though, a valve inside the bov opens to release the excess pressure in the system and prevent all that compressed air from back-flowing into the compressor. if you want to see diagrams of actual bovs, go here: www.blowoffvalves.com.

a bypass valve (bpv) is basically a bov. the difference is that instead of releasing all that air into the atmosphere, it sends it back into the intake tract, BEFORE the comrpessor but AFTER the mass air flow sensor (maf). many maf-equipped cars use this because it prevents them from stalling out. many race cars use this because it aids in faster spool-up time between shifts. if you really wanna know the whole business behind all this stalling stuff, pm me and i'll help ya out :).

the msp is already equipped with a bpv....that's what causes the so-called "turkey" sound our cars are known for. you can see it quite easily if you pop the hood. trace your turbocharger piping and you'll see a hose coming off of the turbo-to-intercooler pipe that leads to a small circular looking thing (that's the bpv) and another hose which leads from the bpv to the intake piping. now something really interesting happens when you add an intake...that turkey gets freakin loud! search around the forums, there's a couple soundclips of it.

now you mentioned you were looking for a sound like a quick release of air....like a pssssht sound. www.blowoffvalves.com has soundclips of a bunch of bovs. but if you're looking for a straight air sound with no bells or whistles, a couple ones to consider would be: blitz dual drive, apexi bov, tial bov (i think it's called the raptor), any turboxs bov, hks super sequential (provided you go with the purple insert). you may also want to look into the bov kit made by forge motorsports. it's specific to our car....search the forums for more info. i'm not sure how the greddy rs sounds....never heard one before.

certain bovs can produce a whistling type sound if you're into that. if you ever watched fast & the furious (don't lie, we all did), that whistling sound the green eclipse makes....that's a greddy type-s bov. the hks ssqv makes a similar but very distinct sound.

hope that answers most of your questions.

that has to be one of the best replies ever I learned more in that post then I ever thought I could learn in one post awesome u my friend are definately a plus to this forum
 
Striker187 said:
first thing's first. it sounds like you don't really understand how a turbocharger system works. www.howstuffworks.com has a writeup if i recall correctly. read that first :).

ok now that you've read that, here's the reason for using a blow off valve. when the throttle is open and the turbo is compressing air, everything's great. now when you take your foot off of the accelerator and close the throttle plate, all that compressed air slams up against and has nowhere to go except backwards. it ends up flowing backwards into the compressor....which is spinning at probably 20k-30k and upwards (some turbines spin at 100k and higher). doesn't sound like a pretty picture huh? the compressor will be forced to slow down severely, making spool-up time between shifts longer and can damage the compressor over time.

a bov is basically a controlled leak in your turbocharger system. when the throttle plate is open, the bov stays closed. when you close the plate though, a valve inside the bov opens to release the excess pressure in the system and prevent all that compressed air from back-flowing into the compressor. if you want to see diagrams of actual bovs, go here: www.blowoffvalves.com.

a bypass valve (bpv) is basically a bov. the difference is that instead of releasing all that air into the atmosphere, it sends it back into the intake tract, BEFORE the comrpessor but AFTER the mass air flow sensor (maf). many maf-equipped cars use this because it prevents them from stalling out. many race cars use this because it aids in faster spool-up time between shifts. if you really wanna know the whole business behind all this stalling stuff, pm me and i'll help ya out :).

the msp is already equipped with a bpv....that's what causes the so-called "turkey" sound our cars are known for. you can see it quite easily if you pop the hood. trace your turbocharger piping and you'll see a hose coming off of the turbo-to-intercooler pipe that leads to a small circular looking thing (that's the bpv) and another hose which leads from the bpv to the intake piping. now something really interesting happens when you add an intake...that turkey gets freakin loud! search around the forums, there's a couple soundclips of it.

now you mentioned you were looking for a sound like a quick release of air....like a pssssht sound. www.blowoffvalves.com has soundclips of a bunch of bovs. but if you're looking for a straight air sound with no bells or whistles, a couple ones to consider would be: blitz dual drive, apexi bov, tial bov (i think it's called the raptor), any turboxs bov, hks super sequential (provided you go with the purple insert). you may also want to look into the bov kit made by forge motorsports. it's specific to our car....search the forums for more info. i'm not sure how the greddy rs sounds....never heard one before.

certain bovs can produce a whistling type sound if you're into that. if you ever watched fast & the furious (don't lie, we all did), that whistling sound the green eclipse makes....that's a greddy type-s bov. the hks ssqv makes a similar but very distinct sound.

hope that answers most of your questions.

U are a car GOD...thanks for the info u just taught me everything i kno about bov...granted it was jus general info. but it was more than i knew...thanks alot. U and msphtown have both been a big help.
 
Striker187 said:
haha far from a car god, but thanks :). i do my best to be helpful. any other questions, lemme know.

I was listening to some sound clips of the HKS SSQ BOV...that is exactly the sound i am looking for. What all do i need to purchase in order to apply that bov to my MSP?...do i need any kinda of special application, kit, etc.
 
speedmo21 said:
hey whats up.ive got a turboxs boost controller..ive got it set around 9psi..im lookin into bovs and really want the turboxs RFL bov...however it says for use w/cars pushin 10-25psi...should i still get the rfl..or any other suggestions of a nice soundin bov

Just use it regardless...

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I would recomend at the very least getting the upper hardpipe that someone sells... I forget who makes it. then you can mount the HKS properly.

but inreality I would suggest either a SMIC or FMIC kit. but its a lot more money
 
Striker187 said:
haha far from a car god, but thanks :). i do my best to be helpful. any other questions, lemme know.

I also was looking into lowering my car...what is a good brand of springs to use?
 
RyanJayG said:
I would recomend at the very least getting the upper hardpipe that someone sells... I forget who makes it. then you can mount the HKS properly.

but inreality I would suggest either a SMIC or FMIC kit. but its a lot more money

Hey thanx for the advise...do u kno anything about lowering springs? What are some good kits if u kno any? And when u say smic and fmic kits is that the same as a fc and fd kit?
 
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03mazdashawty said:
Hey thanx for the advise...do u kno anything about lowering springs? What are some good kits if u kno any? And when u say smic and fmic kits is that the same as a fc and fd kit?

not exactly the same a RX7 kits, but the same general idea. hardpipes, upgraded intercooler, BOV, etc.

the routing, and size reqirements are different car to car. there are several options for MSP's

for lowering springs you can't really go wrong with a name brand.. be very wary of anything "e-bay" brand.

stick with the big names and you'll be ok.

fist off with springs though, is how low do you want to go? many people are perfectly happy with the eibach prokit's moderate drop, but there are others that drop much more. then there are coilovers like what I have... its basically the only way to get as low as I am, becasue you'd kill your struts trying to go this low without adjustability.
 
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