BOV - truths - education

[kryptto]

Hey all,

New to this forum, I am looking to be schooled on the blow off valve.  I have heard many say - great for an effect - no benefits.  Have heard others tell stories about performance - any chance someone can school me on this discussion? 

Have a tuned 2014 27K  - typical bolt on's, CAI - 170 Thermostat - 3 BAR MAP - catch can - cold range plugs - others I am forgetting.

Thanks

[bpd1151]

Welcome aboard .......

What info are you looking for?

Sent from my SM-N986U1 using Tapatalk

[Ecoboost_xsport]

Hey all,

New to this forum, I am looking to be schooled on the blow off valve.  I have heard many say - great for an effect - no benefits.  Have heard others tell stories about performance - any chance someone can school me on this discussion? 

Have a tuned 2014 27K  - typical bolt on's, CAI - 170 Thermostat - 3 BAR MAP - catch can - cold range plugs - others I am forgetting.

Thanks

All turbocharged vehicles have a BOV (sometimes called a divertor or bypass valve), it's just referred to differently, depending on who you speak with.  The term "BOV" USUALLY refers to Venting To Atmosphere, though, which is what I'm assuming you are curious about. Whether that is done by modifying the stock BOV or installing an aftermarket one, the concept is the same.


Class is in session:


1) Essentially there are 2 ways to "meter" the fuel in a vehicle.  One method is to use a Mass Air Flow sensor (MAF) and the other is to use a Manifold Absolute Pressure sensor (MAP).  MAF uses the flow of air across an element to measure this, while a MAP uses a pressure transducer to measure how high the pressure in the system is (called a "speed density" system).


2) A BOV, or divertor/bypass valve, is designed to release any excess pressure buildup beyond what the system is calling for at any given moment.  Excessive pressure buildup can cause turbo-flutter and really kills power by making your turbo less efficient (overly simplified explanation) and can prematurely kill the turbo. In both types of fuel-delivery systems (MAF & MAP), the BOV diverts air back into the intake system, but for different reasons. A MAF-based system diverts this air back into the system because it has already been "measured" and, thus, is required in order to achieve the correct AFRs in the system.  If you dump that air into the atmosphere in a MAF system, it can throw off the fuel measurements because the system has counted that air and is adding fuel accordingly.  Without it, now the mixture is rich...and robbing power.  That being said, many people still VTA MAF-based systems as the effect can be minor in some cases or it is tuned-out by an aftermarket tune. VERDICT:  I'd be careful VTA a MAF-based system.


3) That leads us to a MAP-based system.  It reads pressure within the system and the fuel measurement is taken before the valve is opened to release that excess pressure I mentioned earlier.  So why does it divert air back into the intake system? No real reason other than to satisfy emissions compliance and to remove NVH (Noise, Vibration, Harmonics).  Majority of car owners want their cars quiet, and that diversion back into the system keeps the noise down.  As for emissions compliance, the air inside the intake system can sometimes carry contaminants such as oil vapor, especially if a turbo is beginning to fail.  So instead of polluting the atmosphere, the EPA mandates that we destroy our engines instead, LOL.  VERDICT: Basically, there is no performance reason why you need to divert the air back into the system on a MAP-based, speed density platform...it's harmless, VTA to your hearts content.


4)  Most turbocharged vehicles utilize speed density while most NA platforms use the MAF technique.  AFAIK, all ecoboost engines use this method, so you're good to go.

I may have overly-simplified the explanation, but it was done for effect.  I'm sure there are exceptions to the rule, so for the engineers in here that may pick apart my explanation, just know that I'm aware there is more nuance than what I've described.

[kryptto]

Hey all,

New to this forum, I am looking to be schooled on the blow off valve.  I have heard many say - great for an effect - no benefits.  Have heard others tell stories about performance - any chance someone can school me on this discussion? 

Have a tuned 2014 27K  - typical bolt on's, CAI - 170 Thermostat - 3 BAR MAP - catch can - cold range plugs - others I am forgetting.

Thanks

All turbocharged vehicles have a BOV (sometimes called a divertor or bypass valve), it's just referred to differently, depending on who you speak with.  The term "BOV" USUALLY refers to Venting To Atmosphere, though, which is what I'm assuming you are curious about. Whether that is done by modifying the stock BOV or installing an aftermarket one, the concept is the same.


Class is in session:


1) Essentially there are 2 ways to "meter" the fuel in a vehicle.  One method is to use a Mass Air Flow sensor (MAF) and the other is to use a Manifold Absolute Pressure sensor (MAP).  MAF uses the flow of air across an element to measure this, while a MAP uses a pressure transducer to measure how high the pressure in the system is (called a "speed density" system).


2) A BOV, or divertor/bypass valve, is designed to release any excess pressure buildup beyond what the system is calling for at any given moment.  Excessive pressure buildup can cause turbo-flutter and really kills power by making your turbo less efficient (overly simplified explanation) and can prematurely kill the turbo. In both types of fuel-delivery systems (MAF & MAP), the BOV diverts air back into the intake system, but for different reasons. A MAF-based system diverts this air back into the system because it has already been "measured" and, thus, is required in order to achieve the correct AFRs in the system.  If you dump that air into the atmosphere in a MAF system, it can throw off the fuel measurements because the system has counted that air and is adding fuel accordingly.  Without it, now the mixture is rich...and robbing power.  That being said, many people still VTA MAF-based systems as the effect can be minor in some cases or it is tuned-out by an aftermarket tune. VERDICT:  I'd be careful VTA a MAF-based system.


3) That leads us to a MAP-based system.  It reads pressure within the system and the fuel measurement is taken before the valve is opened to release that excess pressure I mentioned earlier.  So why does it divert air back into the intake system? No real reason other than to satisfy emissions compliance and to remove NVH (Noise, Vibration, Harmonics).  Majority of car owners want their cars quiet, and that diversion back into the system keeps the noise down.  As for emissions compliance, the air inside the intake system can sometimes carry contaminants such as oil vapor, especially if a turbo is beginning to fail.  So instead of polluting the atmosphere, the EPA mandates that we destroy our engines instead, LOL.  VERDICT: Basically, there is no performance reason why you need to divert the air back into the system on a MAP-based, speed density platform...it's harmless, VTA to your hearts content.


4)  Most turbocharged vehicles utilize speed density while most NA platforms use the MAF technique.  AFAIK, all ecoboost engines use this method, so you're good to go.

I may have overly-simplified the explanation, but it was done for effect.  I'm sure there are exceptions to the rule, so for the engineers in here that may pick apart my explanation, just know that I'm aware there is more nuance than what I've described.

First off, thank you very much for that explanation.  In my 50s now, working on these complicated engines can be intimidating and misinformation like poison. 

So I run cattless, J&L catch can,  if I follow the logic, the VTA is better for the carbon build up in the intake common with this engine, however the car under the hood will get louder when the pressure builds and bleeds off.  I check off both as a I don't care - cattless and blow out the harmful contaminants.  This is NOT a daily driver and has 27K original miles.

Next Q what type of replacement do I need to VTA, I lean to safe and conservative.  Do I assume there is just one?

Thanks again

Sent from my SM-T860 using Tapatalk

[kryptto]

So I found https://www.boombaracing.com/taurus-sho-2010-2019/?page=1#0

Assuming others have used them. They are 100% BOV.

I came across this YT video covering 50/50 bov.  Thoughts?



Based on the tutorial provided here Ford is using 100% recirculating.  50/50 a better option potentially?

Anyone know if these are 50/50 spacer?

https://www.vividracing.com/turbo-supercharger-c-4266.html

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[Ecoboost_xsport]

OK, so in this particular platform, there are electronic bypassertor valves.  There are 2 valves, one for each turbo.  You can do the cheapest and easiest route.  Go to a hardware store and buy two 1" chair leg caps.  Open your hood, remove the BOV-to-intake hose and place the chair leg cap onto the intake side.  Just leave BOV open...to.... atmosphere. No harm, no foul.


You can get a bit more expensive with the adapter plates, but to me they are pointless.  Either go all the way or don't do it at all.  Again, in this platform it has zero effect on performance.  You are ONLY gaining some cool "Psssfffff" noises".


Something to understand.  Since these are electronic, they behave slightly different than the traditional vacuum-referenced style.  Instead of blowing off only when getting off the throttle, these valves will open intermittently at, what some consider, weird times.  It's not how traditional BOVs open but it is 100% normal in this application.  The PCM is telling the BOV to open when it identifies inefficient boost levels, instead of the more traditional way of having a vacuum line attached to the top.


Just VTA to your hearts content.  There is no "conservative" or "extreme" way to do this.  You either do it, or don't...either way will not affect the car.

Hey all,

New to this forum, I am looking to be schooled on the blow off valve.  I have heard many say - great for an effect - no benefits.  Have heard others tell stories about performance - any chance someone can school me on this discussion? 

Have a tuned 2014 27K  - typical bolt on's, CAI - 170 Thermostat - 3 BAR MAP - catch can - cold range plugs - others I am forgetting.

Thanks

All turbocharged vehicles have a BOV (sometimes called a divertor or bypass valve), it's just referred to differently, depending on who you speak with.  The term "BOV" USUALLY refers to Venting To Atmosphere, though, which is what I'm assuming you are curious about. Whether that is done by modifying the stock BOV or installing an aftermarket one, the concept is the same.


Class is in session:


1) Essentially there are 2 ways to "meter" the fuel in a vehicle.  One method is to use a Mass Air Flow sensor (MAF) and the other is to use a Manifold Absolute Pressure sensor (MAP).  MAF uses the flow of air across an element to measure this, while a MAP uses a pressure transducer to measure how high the pressure in the system is (called a "speed density" system).


2) A BOV, or divertor/bypass valve, is designed to release any excess pressure buildup beyond what the system is calling for at any given moment.  Excessive pressure buildup can cause turbo-flutter and really kills power by making your turbo less efficient (overly simplified explanation) and can prematurely kill the turbo. In both types of fuel-delivery systems (MAF & MAP), the BOV diverts air back into the intake system, but for different reasons. A MAF-based system diverts this air back into the system because it has already been "measured" and, thus, is required in order to achieve the correct AFRs in the system.  If you dump that air into the atmosphere in a MAF system, it can throw off the fuel measurements because the system has counted that air and is adding fuel accordingly.  Without it, now the mixture is rich...and robbing power.  That being said, many people still VTA MAF-based systems as the effect can be minor in some cases or it is tuned-out by an aftermarket tune. VERDICT:  I'd be careful VTA a MAF-based system.


3) That leads us to a MAP-based system.  It reads pressure within the system and the fuel measurement is taken before the valve is opened to release that excess pressure I mentioned earlier.  So why does it divert air back into the intake system? No real reason other than to satisfy emissions compliance and to remove NVH (Noise, Vibration, Harmonics).  Majority of car owners want their cars quiet, and that diversion back into the system keeps the noise down.  As for emissions compliance, the air inside the intake system can sometimes carry contaminants such as oil vapor, especially if a turbo is beginning to fail.  So instead of polluting the atmosphere, the EPA mandates that we destroy our engines instead, LOL.  VERDICT: Basically, there is no performance reason why you need to divert the air back into the system on a MAP-based, speed density platform...it's harmless, VTA to your hearts content.


4)  Most turbocharged vehicles utilize speed density while most NA platforms use the MAF technique.  AFAIK, all ecoboost engines use this method, so you're good to go.

I may have overly-simplified the explanation, but it was done for effect.  I'm sure there are exceptions to the rule, so for the engineers in here that may pick apart my explanation, just know that I'm aware there is more nuance than what I've described.

First off, thank you very much for that explanation.  In my 50s now, working on these complicated engines can be intimidating and misinformation like poison. 

So I run cattless, J&L catch can,  if I follow the logic, the VTA is better for the carbon build up in the intake common with this engine, however the car under the hood will get louder when the pressure builds and bleeds off.  I check off both as a I don't care - cattless and blow out the harmful contaminants.  This is NOT a daily driver and has 27K original miles.

Next Q what type of replacement do I need to VTA, I lean to safe and conservative.  Do I assume there is just one?

Thanks again

Sent from my SM-T860 using Tapatalk

[kryptto]

OK, so in this particular platform, there are electronic bypassertor valves.  There are 2 valves, one for each turbo.  You can do the cheapest and easiest route.  Go to a hardware store and buy two 1" chair leg caps.  Open your hood, remove the BOV-to-intake hose and place the chair leg cap onto the intake side.  Just leave BOV open...to.... atmosphere. No harm, no foul.


You can get a bit more expensive with the adapter plates, but to me they are pointless.  Either go all the way or don't do it at all.  Again, in this platform it has zero effect on performance.  You are ONLY gaining some cool "Psssfffff" noises".


Something to understand.  Since these are electronic, they behave slightly different than the traditional vacuum-referenced style.  Instead of blowing off only when getting off the throttle, these valves will open intermittently at, what some consider, weird times.  It's not how traditional BOVs open but it is 100% normal in this application.  The PCM is telling the BOV to open when it identifies inefficient boost levels, instead of the more traditional way of having a vacuum line attached to the top.


Just VTA to your hearts content.  There is no "conservative" or "extreme" way to do this.  You either do it, or don't...either way will not affect the car.

Hey all,

New to this forum, I am looking to be schooled on the blow off valve.  I have heard many say - great for an effect - no benefits.  Have heard others tell stories about performance - any chance someone can school me on this discussion? 

Have a tuned 2014 27K  - typical bolt on's, CAI - 170 Thermostat - 3 BAR MAP - catch can - cold range plugs - others I am forgetting.

Thanks

All turbocharged vehicles have a BOV (sometimes called a divertor or bypass valve), it's just referred to differently, depending on who you speak with.  The term "BOV" USUALLY refers to Venting To Atmosphere, though, which is what I'm assuming you are curious about. Whether that is done by modifying the stock BOV or installing an aftermarket one, the concept is the same.


Class is in session:


1) Essentially there are 2 ways to "meter" the fuel in a vehicle.  One method is to use a Mass Air Flow sensor (MAF) and the other is to use a Manifold Absolute Pressure sensor (MAP).  MAF uses the flow of air across an element to measure this, while a MAP uses a pressure transducer to measure how high the pressure in the system is (called a "speed density" system).


2) A BOV, or divertor/bypass valve, is designed to release any excess pressure buildup beyond what the system is calling for at any given moment.  Excessive pressure buildup can cause turbo-flutter and really kills power by making your turbo less efficient (overly simplified explanation) and can prematurely kill the turbo. In both types of fuel-delivery systems (MAF & MAP), the BOV diverts air back into the intake system, but for different reasons. A MAF-based system diverts this air back into the system because it has already been "measured" and, thus, is required in order to achieve the correct AFRs in the system.  If you dump that air into the atmosphere in a MAF system, it can throw off the fuel measurements because the system has counted that air and is adding fuel accordingly.  Without it, now the mixture is rich...and robbing power.  That being said, many people still VTA MAF-based systems as the effect can be minor in some cases or it is tuned-out by an aftermarket tune. VERDICT:  I'd be careful VTA a MAF-based system.


3) That leads us to a MAP-based system.  It reads pressure within the system and the fuel measurement is taken before the valve is opened to release that excess pressure I mentioned earlier.  So why does it divert air back into the intake system? No real reason other than to satisfy emissions compliance and to remove NVH (Noise, Vibration, Harmonics).  Majority of car owners want their cars quiet, and that diversion back into the system keeps the noise down.  As for emissions compliance, the air inside the intake system can sometimes carry contaminants such as oil vapor, especially if a turbo is beginning to fail.  So instead of polluting the atmosphere, the EPA mandates that we destroy our engines instead, LOL.  VERDICT: Basically, there is no performance reason why you need to divert the air back into the system on a MAP-based, speed density platform...it's harmless, VTA to your hearts content.


4)  Most turbocharged vehicles utilize speed density while most NA platforms use the MAF technique.  AFAIK, all ecoboost engines use this method, so you're good to go.

I may have overly-simplified the explanation, but it was done for effect.  I'm sure there are exceptions to the rule, so for the engineers in here that may pick apart my explanation, just know that I'm aware there is more nuance than what I've described.

First off, thank you very much for that explanation.  In my 50s now, working on these complicated engines can be intimidating and misinformation like poison. 

So I run cattless, J&L catch can,  if I follow the logic, the VTA is better for the carbon build up in the intake common with this engine, however the car under the hood will get louder when the pressure builds and bleeds off.  I check off both as a I don't care - cattless and blow out the harmful contaminants.  This is NOT a daily driver and has 27K original miles.

Next Q what type of replacement do I need to VTA, I lean to safe and conservative.  Do I assume there is just one?

Thanks again

Sent from my SM-T860 using Tapatalk

Thank you!  All good appreciate the input and i saw the YT video of the person using those rubber feet.  Thanks again

Sent from my SM-T860 using Tapatalk

[kryptto]

Hey all, just an update and I am sure it won't be a surprise.  I installed the spacers and the guy I worked with for tuning noticed my charge temps were down after even a few WOT runs.  So a good benefit, nonetheless.  Thanks again.

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