To BOV or not
10-16-2017, 05:09 PM
#1
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Thread Starter
To BOV or not
For those that have tunes, is there any functional pro or con to (Renntech) Blow Off Valves or is it just noise. And if noise, is it subtle and complementary or Rice Burner-like?
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10-16-2017, 07:09 PM
#3
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2020 AMG GTR PRO (Renntech)，2021 Audi RS6 Avant，2017 GLE63S SUV，2022 992 Targa
its more of a noise only. i really like the way the BOV sounds and it sounds like mclaren's turbo spool or pagani... since its a V12 amg.... it won't help you in performance wise tho you would feel like it did.
10-16-2017, 07:47 PM
#4
10-16-2017, 10:21 PM
#5
It's not a performance mod. In fact, it retards performance. The stock setup is what it is for a reason. It recirculates pressurized air back into the manifold to keep the turbos spooled between shifts. This reduces turbo lag. Install the faux BOV (not really a BOV in reality), and you are actually making the car slower just to have a cool sound.
10-16-2017, 11:29 PM
#6
Super Member
It's not a performance mod. In fact, it retards performance. The stock setup is what it is for a reason. It recirculates pressurized air back into the manifold to keep the turbos spooled between shifts. This reduces turbo lag. Install the faux BOV (not really a BOV in reality), and you are actually making the car slower just to have a cool sound.
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10-17-2017, 03:59 AM
#8
Member
It's not a performance mod. In fact, it retards performance. The stock setup is what it is for a reason. It recirculates pressurized air back into the manifold to keep the turbos spooled between shifts. This reduces turbo lag. Install the faux BOV (not really a BOV in reality), and you are actually making the car slower just to have a cool sound.
I do know for a fact that the stock setup circulates back into the airbox, because I did the BOVs, and yes, I'm loving the sound.
10-18-2017, 09:11 AM
#9
I thought I just explained it. Boosted air is recirculated to keep the turbos spooled a bit during gear shifts and when you let off the throttle. Installing an adapter plate with a hole in it negates that effect. The "BOV" products you see on the aftermarket are also not blow off valves. If you want a real blow off valve, you're going to have to change the turbo setup a bit from the stock design. Also, recirculating the air has nothing to do with emissions. That air is 100% atmospheric (albeit pressurized) and has never made it past the engine's throttle opening. Recirculating it back into the system does nothing for the air coming out the tailpipe. The only scenario in which it might affect emissions is when the air sensor is located before the point of recirculation. In that case, the sensor has already "seen" and metered that air, only to have it recirculated without the sensor seeing it. This can cause some issues. In applications where this is the case, most people will move the air sensor to a different location. In the AMG GT cars, this isn't a problem.
A real BOV (which these products are not) is used when you run really high boost. They prevent compressor surge—when you let off the throttle and the throttle plate closes, sending pressurized air back toward the turbo, causing it to stall. Not using one on these cars can cause hoses and pipes to rupture due to the high back-pressure. This doesn't happen on GT-class cars cars since they aren't running boost high enough.
You are spending money on a fake product. It mimics the BOV sound, but does nothing for performance.
Exactly. You are enjoying the SOUND. And nothing more. If that makes you happy, awesome. But understand how and why the thing does what it does. No, the air doesn't go back directly into the intake manifold. I misspoke about that part.
Here is a quote from another thread about this same thing: https://mbworld.org/forums/c-class-w...v-pshhh-2.html The thread is in reference to the W205 engine, but the principles should hold true with the GT-class as well, unless there is an inherent forced-induction design change I'm not aware of. The physical location of the turbos doesn't matter.
"This mod is total nonsense. The valve in question is not a blow-off valve. It is a priority valve (or compressor by-pass) that prevents turbo lag. Besides making more noise, letting that air escape to atmosphere increases turbo lag and deadens throttle response, because it defeats the action of the stock design.
Priority valves were first fitted to the Porsche 944 Turbo in 1988. Prior to that everyone used blow-off valves, where needed. Any company since, that made a good turbo system, used the priority valve setup. Audi, Porsche and Subaru are legendary examples. Priority valves are so important I actually welded fittings to my 1988 Celica GT-4 intercooler and intake box to adapt the clever Porsche 944/Audi part! Much improved the throttle response.
Now, racing turbo systems over about 2.5 bar do require a blow-off valve in addition to the priority valve function. Otherwise, the over-pressure in the intake risks splitting intercooler seams or blowing off hoses. The C-Class turbo systems are nowhere near requiring this mechanical pressure relief. The opposite is true. We want to keep that pressurized air working for us, not just **** it away.
Installing an aftermarket 'blow-off valve' defeats the clever function of the stock priority valve. The priority valve is there to remove turbo lag. It does this by recirculating the compressed air back into the atmospheric side. This keeps the compressor from stalling, so when you tip back into the throttle, it makes boost instantly. This is just as true at part throttle as full throttle. It works all the time.
There is also a very clever, simple delay spring built into the system, such that this factory priority valve system, once pulled open by manifold vacuum, resists closing for ~.1 to .3 seconds due to the resistance of this spring. This delay allows the turbocharger to spin up freely (no load) for an instant. As the valve comes completely closed, the turbine is now almost up to full rotational speed, so there is more boost available, much more when opening the throttle that without it.
If you want to understand this theory, put your hand over the suction of a household vacuum cleaner. The speed of the motor rises dramatically because, although still pulling a vacuum, it is doing no work (no air is moving). That is what the priority valve does for the turbocharger, specifically by adding pressure to the atmospheric side of the compressor wheel. It lets it freewheel momentarily and not loose rotational speed. Most important is the spring delay speeds up the turbine wheel further by there being no load on the compressor side.
-=m=-"
A real BOV (which these products are not) is used when you run really high boost. They prevent compressor surge—when you let off the throttle and the throttle plate closes, sending pressurized air back toward the turbo, causing it to stall. Not using one on these cars can cause hoses and pipes to rupture due to the high back-pressure. This doesn't happen on GT-class cars cars since they aren't running boost high enough.
You are spending money on a fake product. It mimics the BOV sound, but does nothing for performance.
I do know for a fact that the stock setup circulates back into the airbox, because I did the BOVs, and yes, I'm loving the sound.
Here is a quote from another thread about this same thing: https://mbworld.org/forums/c-class-w...v-pshhh-2.html The thread is in reference to the W205 engine, but the principles should hold true with the GT-class as well, unless there is an inherent forced-induction design change I'm not aware of. The physical location of the turbos doesn't matter.
"This mod is total nonsense. The valve in question is not a blow-off valve. It is a priority valve (or compressor by-pass) that prevents turbo lag. Besides making more noise, letting that air escape to atmosphere increases turbo lag and deadens throttle response, because it defeats the action of the stock design.
Priority valves were first fitted to the Porsche 944 Turbo in 1988. Prior to that everyone used blow-off valves, where needed. Any company since, that made a good turbo system, used the priority valve setup. Audi, Porsche and Subaru are legendary examples. Priority valves are so important I actually welded fittings to my 1988 Celica GT-4 intercooler and intake box to adapt the clever Porsche 944/Audi part! Much improved the throttle response.
Now, racing turbo systems over about 2.5 bar do require a blow-off valve in addition to the priority valve function. Otherwise, the over-pressure in the intake risks splitting intercooler seams or blowing off hoses. The C-Class turbo systems are nowhere near requiring this mechanical pressure relief. The opposite is true. We want to keep that pressurized air working for us, not just **** it away.
Installing an aftermarket 'blow-off valve' defeats the clever function of the stock priority valve. The priority valve is there to remove turbo lag. It does this by recirculating the compressed air back into the atmospheric side. This keeps the compressor from stalling, so when you tip back into the throttle, it makes boost instantly. This is just as true at part throttle as full throttle. It works all the time.
There is also a very clever, simple delay spring built into the system, such that this factory priority valve system, once pulled open by manifold vacuum, resists closing for ~.1 to .3 seconds due to the resistance of this spring. This delay allows the turbocharger to spin up freely (no load) for an instant. As the valve comes completely closed, the turbine is now almost up to full rotational speed, so there is more boost available, much more when opening the throttle that without it.
If you want to understand this theory, put your hand over the suction of a household vacuum cleaner. The speed of the motor rises dramatically because, although still pulling a vacuum, it is doing no work (no air is moving). That is what the priority valve does for the turbocharger, specifically by adding pressure to the atmospheric side of the compressor wheel. It lets it freewheel momentarily and not loose rotational speed. Most important is the spring delay speeds up the turbine wheel further by there being no load on the compressor side.
-=m=-"
Last edited by FourT6and2; 10-18-2017 at 09:31 AM.
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10-20-2017, 09:58 PM
#10
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Thread Starter
Guys, thanks for the confirmation. As suspected. I won't install them. I was only curious because Renntech claims 70% of their tune purchasers include them. They didn't try to make any performance claims.
10-20-2017, 10:09 PM
#11
Yeah, I don't doubt that 70% number. A lot of people probably do it because it sounds cool.
10-21-2017, 06:58 PM
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2017 C63s AMG - 2011 CL65 AMG - 2015 G63 AMG
Please help me understand, I am confused as to why venting to atmosphere would reduce performance.
If you really want to get technical, I feel that the small amount of air that isn't going directly into the intake, might require the car to pull more air through the filter in order to have the same mass of air to create boost. However, this is such a small amount of air. Similarly, you could theoretically say the vented to atmosphere car has a benefit since the excess air that is vented is usually at a higher temperature than atmospheric air, and therefore it increases IAT. Again, this would be such a negligible difference since the amount of air is so small that it wouldn't matter.
I thought I just explained it. Boosted air is recirculated to keep the turbos spooled a bit during gear shifts and when you let off the throttle. Installing an adapter plate with a hole in it negates that effect. The "BOV" products you see on the aftermarket are also not blow off valves. If you want a real blow off valve, you're going to have to change the turbo setup a bit from the stock design. Also, recirculating the air has nothing to do with emissions. That air is 100% atmospheric (albeit pressurized) and has never made it past the engine's throttle opening. Recirculating it back into the system does nothing for the air coming out the tailpipe. The only scenario in which it might affect emissions is when the air sensor is located before the point of recirculation. In that case, the sensor has already "seen" and metered that air, only to have it recirculated without the sensor seeing it. This can cause some issues. In applications where this is the case, most people will move the air sensor to a different location. In the AMG GT cars, this isn't a problem.
I understand that when a car has a MAF sensor, that is a big reason not to run the car with the valve vented to atmosphere. Because the MAF sensor helps the ECU calculate the correct amount of fuel to use, and once the air is let out to the atmosphere, the car runs rich for a second. Recirculating it back allows for the correct air fuel mixture. But the AMG GT (and C63s, which I own, does not have a MAF sensor so none of this matters for this application.
A real BOV (which these products are not) is used when you run really high boost. They prevent compressor surge—when you let off the throttle and the throttle plate closes, sending pressurized air back toward the turbo, causing it to stall. Not using one on these cars can cause hoses and pipes to rupture due to the high back-pressure. This doesn't happen on GT-class cars cars since they aren't running boost high enough.
Doesn't it not happen because the stock diverter valve opens up, releasing the pressurized air into the non-pressurized intake box? I don't think the air is pressurizing the intake box before the turbo, where it is being recirculated to.
You are spending money on a fake product. It mimics the BOV sound, but does nothing for performance.
I understand it doesn't add performance, but I am confused on how it detracts performance.
Exactly. You are enjoying the SOUND. And nothing more. If that makes you happy, awesome. But understand how and why the thing does what it does. No, the air doesn't go back directly into the intake manifold. I misspoke about that part.
Here is a quote from another thread about this same thing: https://mbworld.org/forums/c-class-w...v-pshhh-2.html The thread is in reference to the W205 engine, but the principles should hold true with the GT-class as well, unless there is an inherent forced-induction design change I'm not aware of. The physical location of the turbos doesn't matter.
"This mod is total nonsense. The valve in question is not a blow-off valve. It is a priority valve (or compressor by-pass) that prevents turbo lag. Besides making more noise, letting that air escape to atmosphere increases turbo lag and deadens throttle response, because it defeats the action of the stock design.
Priority valves were first fitted to the Porsche 944 Turbo in 1988. Prior to that everyone used blow-off valves, where needed. Any company since, that made a good turbo system, used the priority valve setup. Audi, Porsche and Subaru are legendary examples. Priority valves are so important I actually welded fittings to my 1988 Celica GT-4 intercooler and intake box to adapt the clever Porsche 944/Audi part! Much improved the throttle response.
Now, racing turbo systems over about 2.5 bar do require a blow-off valve in addition to the priority valve function. Otherwise, the over-pressure in the intake risks splitting intercooler seams or blowing off hoses. The C-Class turbo systems are nowhere near requiring this mechanical pressure relief. The opposite is true. We want to keep that pressurized air working for us, not just **** it away.
Installing an aftermarket 'blow-off valve' defeats the clever function of the stock priority valve. The priority valve is there to remove turbo lag. It does this by recirculating the compressed air back into the atmospheric side. This keeps the compressor from stalling, so when you tip back into the throttle, it makes boost instantly. This is just as true at part throttle as full throttle. It works all the time.
I think the reason it keeps the compressor from stalling is that when it opens, pressurized air does not go back towards the turbo itself as a means of expansion, and therefore doesn't force the compressor wheel to stall or go backwards in order to escape. How would venting to atmosphere stop this? If is recirculating compressed air, as soon as the valve opens up, the air is not compressed anymore, since it is going back to the intake box where the air is not compressed, before the turbo, correct?
There is also a very clever, simple delay spring built into the system, such that this factory priority valve system, once pulled open by manifold vacuum, resists closing for ~.1 to .3 seconds due to the resistance of this spring. This delay allows the turbocharger to spin up freely (no load) for an instant. As the valve comes completely closed, the turbine is now almost up to full rotational speed, so there is more boost available, much more when opening the throttle that without it.
Venting to atmosphere wouldn't stop this from happening, would it, since it is a property of the priority valve itself? That priority valve is still in the car...
If you want to understand this theory, put your hand over the suction of a household vacuum cleaner. The speed of the motor rises dramatically because, although still pulling a vacuum, it is doing no work (no air is moving). That is what the priority valve does for the turbocharger, specifically by adding pressure to the atmospheric side of the compressor wheel. It lets it freewheel momentarily and not loose rotational speed. Most important is the spring delay speeds up the turbine wheel further by there being no load on the compressor side.
-=m=-"
I understand that when a car has a MAF sensor, that is a big reason not to run the car with the valve vented to atmosphere. Because the MAF sensor helps the ECU calculate the correct amount of fuel to use, and once the air is let out to the atmosphere, the car runs rich for a second. Recirculating it back allows for the correct air fuel mixture. But the AMG GT (and C63s, which I own, does not have a MAF sensor so none of this matters for this application.
A real BOV (which these products are not) is used when you run really high boost. They prevent compressor surge—when you let off the throttle and the throttle plate closes, sending pressurized air back toward the turbo, causing it to stall. Not using one on these cars can cause hoses and pipes to rupture due to the high back-pressure. This doesn't happen on GT-class cars cars since they aren't running boost high enough.
Doesn't it not happen because the stock diverter valve opens up, releasing the pressurized air into the non-pressurized intake box? I don't think the air is pressurizing the intake box before the turbo, where it is being recirculated to.
You are spending money on a fake product. It mimics the BOV sound, but does nothing for performance.
I understand it doesn't add performance, but I am confused on how it detracts performance.
Exactly. You are enjoying the SOUND. And nothing more. If that makes you happy, awesome. But understand how and why the thing does what it does. No, the air doesn't go back directly into the intake manifold. I misspoke about that part.
Here is a quote from another thread about this same thing: https://mbworld.org/forums/c-class-w...v-pshhh-2.html The thread is in reference to the W205 engine, but the principles should hold true with the GT-class as well, unless there is an inherent forced-induction design change I'm not aware of. The physical location of the turbos doesn't matter.
"This mod is total nonsense. The valve in question is not a blow-off valve. It is a priority valve (or compressor by-pass) that prevents turbo lag. Besides making more noise, letting that air escape to atmosphere increases turbo lag and deadens throttle response, because it defeats the action of the stock design.
Priority valves were first fitted to the Porsche 944 Turbo in 1988. Prior to that everyone used blow-off valves, where needed. Any company since, that made a good turbo system, used the priority valve setup. Audi, Porsche and Subaru are legendary examples. Priority valves are so important I actually welded fittings to my 1988 Celica GT-4 intercooler and intake box to adapt the clever Porsche 944/Audi part! Much improved the throttle response.
Now, racing turbo systems over about 2.5 bar do require a blow-off valve in addition to the priority valve function. Otherwise, the over-pressure in the intake risks splitting intercooler seams or blowing off hoses. The C-Class turbo systems are nowhere near requiring this mechanical pressure relief. The opposite is true. We want to keep that pressurized air working for us, not just **** it away.
Installing an aftermarket 'blow-off valve' defeats the clever function of the stock priority valve. The priority valve is there to remove turbo lag. It does this by recirculating the compressed air back into the atmospheric side. This keeps the compressor from stalling, so when you tip back into the throttle, it makes boost instantly. This is just as true at part throttle as full throttle. It works all the time.
I think the reason it keeps the compressor from stalling is that when it opens, pressurized air does not go back towards the turbo itself as a means of expansion, and therefore doesn't force the compressor wheel to stall or go backwards in order to escape. How would venting to atmosphere stop this? If is recirculating compressed air, as soon as the valve opens up, the air is not compressed anymore, since it is going back to the intake box where the air is not compressed, before the turbo, correct?
There is also a very clever, simple delay spring built into the system, such that this factory priority valve system, once pulled open by manifold vacuum, resists closing for ~.1 to .3 seconds due to the resistance of this spring. This delay allows the turbocharger to spin up freely (no load) for an instant. As the valve comes completely closed, the turbine is now almost up to full rotational speed, so there is more boost available, much more when opening the throttle that without it.
Venting to atmosphere wouldn't stop this from happening, would it, since it is a property of the priority valve itself? That priority valve is still in the car...
If you want to understand this theory, put your hand over the suction of a household vacuum cleaner. The speed of the motor rises dramatically because, although still pulling a vacuum, it is doing no work (no air is moving). That is what the priority valve does for the turbocharger, specifically by adding pressure to the atmospheric side of the compressor wheel. It lets it freewheel momentarily and not loose rotational speed. Most important is the spring delay speeds up the turbine wheel further by there being no load on the compressor side.
-=m=-"
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Neko 1 (06-21-2020)
10-22-2017, 06:39 PM
#15
Now our engine is a 4.0 liter twin turbo. It's kind of like 2 cla45 engines. Thats why mercedes hinted the potential is easily 700 horses. They won't give us 700 horses because it's not needed and traction.
This is a very non technical common sense way of looking at. They designed the most powerful turbo 4 ever and it needed no blow off valve.
10-23-2017, 04:54 AM
#16
Member
As explained earlier, we know the stock system is designed to recirculat the air back into the intake instead of banging against the Compressor wheel. Why take the air and **** it out to atmosphere????
These cars are don’t make crazy boost in the range of 30 to 60 PSI like Supra for example with giant turbo that move a lot of air, a blow off valve is adequate enough for that engine because it can. But these cars even when modified can use the benefit of using the BYPASS valve to circulate the air back into the system. These cars and not making 1500+ WHP to get away with a blow off valve. Yes, sounds cool but dose not magically make more bower other than sounding cool and giving you a woody. Again, dose not benefit these cars... not making crazy power here. Stick to what works for the application.
These cars are don’t make crazy boost in the range of 30 to 60 PSI like Supra for example with giant turbo that move a lot of air, a blow off valve is adequate enough for that engine because it can. But these cars even when modified can use the benefit of using the BYPASS valve to circulate the air back into the system. These cars and not making 1500+ WHP to get away with a blow off valve. Yes, sounds cool but dose not magically make more bower other than sounding cool and giving you a woody. Again, dose not benefit these cars... not making crazy power here. Stick to what works for the application.
Last edited by 951turbo; 10-23-2017 at 12:44 PM.
10-23-2017, 08:55 AM
#17
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Fascinating discussion talking about artificial noisemakers that do little more than disturb the neighbors and bring unwanted attention on the noisemaker.
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10-23-2017, 12:09 PM
#18
there re are some people who believe that any bolt on they buy adds horse power. They go out and buy half a dozen bolt on parts: air filter, blow off valve, down pipe, exhaust, tune. Then they add up all the manufacturers claims for each part and say "I added this much horsepower"
10-23-2017, 12:15 PM
#19
there re are some people who believe that any bolt on they buy adds horse power. They go out and buy half a dozen bolt on parts: air filter, blow off valve, down pipe, exhaust, tune. Then they add up all the manufacturers claims for each part and say "I added this much horsepower"
10-23-2017, 03:24 PM
#20
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2017 C63s AMG - 2011 CL65 AMG - 2015 G63 AMG
As explained earlier, we know the stock system is designed to recirculat the air back into the intake instead of banging against the Compressor wheel. Why take the air and **** it out to atmosphere????
These cars are don’t make crazy boost in the range of 30 to 60 PSI like Supra for example with giant turbo that move a lot of air, a blow off valve is adequate enough for that engine because it can. But these cars even when modified can use the benefit of using the BYPASS valve to circulate the air back into the system. These cars and not making 1500+ WHP to get away with a blow off valve. Yes, sounds cool but dose not magically make more bower other than sounding cool and giving you a woody. Again, dose not benefit these cars... not making crazy power here. Stick to what works for the application.
These cars are don’t make crazy boost in the range of 30 to 60 PSI like Supra for example with giant turbo that move a lot of air, a blow off valve is adequate enough for that engine because it can. But these cars even when modified can use the benefit of using the BYPASS valve to circulate the air back into the system. These cars and not making 1500+ WHP to get away with a blow off valve. Yes, sounds cool but dose not magically make more bower other than sounding cool and giving you a woody. Again, dose not benefit these cars... not making crazy power here. Stick to what works for the application.
Can you explain to me why pissing the air out into the atmosphere is any different from recirculating the air back into the intake when it comes to stopping the air banging against the compressor wheel? Don't both accomplish the same thing? I am just trying to get an explanation on the benefits of bypass valve vs blow off, NOT benefits of re-circulation vs no bypass valve.
And to the people talking about the stupidity of "artificial noise," the GTS in race mode makes pops and bangs that are ALL artificial, there is no reason to inject more fuel to create those little bangs that "disturb the neighbors and bring unwanted attention to the noisemaker" and yet you bought the car!
Please tell me you do use race mode and aren't one of the people that make me wish there were more passing lanes in the SoCal canyons!
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triblk6spd (07-21-2020)
10-23-2017, 03:50 PM
#21
Yes, I do understand that it won't make MORE Power, but I am struggling to understand why it will lose power? or even create more turbo lag?
Can you explain to me why pissing the air out into the atmosphere is any different from recirculating the air back into the intake when it comes to stopping the air banging against the compressor wheel? Don't both accomplish the same thing? I am just trying to get an explanation on the benefits of bypass valve vs blow off, NOT benefits of re-circulation vs no bypass valve.
Can you explain to me why pissing the air out into the atmosphere is any different from recirculating the air back into the intake when it comes to stopping the air banging against the compressor wheel? Don't both accomplish the same thing? I am just trying to get an explanation on the benefits of bypass valve vs blow off, NOT benefits of re-circulation vs no bypass valve.
Recirculating the air is NOT about stopping air from "banging against the compressor wheel." The purpose of a BLOW OFF VALVE (which is NOT what the products being discussed here are) is for cars running HIGH BOOST. The GT family of cars from AMG do NOT run high boost. Without a blow off valve, cars with HIGH BOOST, will have issues when you let off the throttle because pressurized air will stall the turbo wheel or rupture pipes/hoses. This will not happen with these AMG cars. So a blow off valve is not needed.
Recirculating the air with the type of valve these cars have helps the turbo stay spinning a bit between gear shifts and when you let off the throttle.
Ask yourself this question: if recirculating the air does nothing, why would a large company like Mercedes, that most likely does everything possible to reduce redundant manufacturing procedures in order to save money and reduce cost... why would they utilize a system that does nothing? They wouldn't. That should tell you something about why they chose to use the type of recirculating valve these cars have. It's not for emissions. And it's not to keep the car quiet.
Tell you what, write a letter to Mercedes/AMG engineers and R&D and tell them the way they build the engine is wrong. I'm sure they'd love to know.
Last edited by FourT6and2; 10-23-2017 at 03:54 PM.
10-23-2017, 04:18 PM
#22
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I never claimed to know more than Mercedes AMG engineering. I am just wondering about the system itself, and how it works.
Flow of air through the compressor wheel isn't what creates boost pressure though, it's exhaust gases. I am unconvinced that the split second release of air into the intake box will keep the turbo spooled up, but I could be wrong. Just never heard of this before. Traditionally, anti lag would be used to keep the turbo spooled between shifts.
tell you what, I'll borrow a vbox and record acceleration with and without the system connected and then I'll know for sure since you guys seem kind of hostile since I am just asking questions to better understand.
I think it is an assumption they did not recirculate air for sound reasons. The GLS I drove as a rental had a blow off valve. But I think in the GTS, c63, e63, they spend a lot of time engineering the sound so that it does not sound (or feel) like a turbocharged engine given the iconic heritage of AMGs large naturally aspirated motors.
Flow of air through the compressor wheel isn't what creates boost pressure though, it's exhaust gases. I am unconvinced that the split second release of air into the intake box will keep the turbo spooled up, but I could be wrong. Just never heard of this before. Traditionally, anti lag would be used to keep the turbo spooled between shifts.
tell you what, I'll borrow a vbox and record acceleration with and without the system connected and then I'll know for sure since you guys seem kind of hostile since I am just asking questions to better understand.
I think it is an assumption they did not recirculate air for sound reasons. The GLS I drove as a rental had a blow off valve. But I think in the GTS, c63, e63, they spend a lot of time engineering the sound so that it does not sound (or feel) like a turbocharged engine given the iconic heritage of AMGs large naturally aspirated motors.
10-23-2017, 04:45 PM
#23
Flow of air through the compressor wheel isn't what creates boost pressure though,
I am unconvinced that the split second release of air into the intake box will keep the turbo spooled up
but I could be wrong.
The bottom line here is all these companies selling these fake blow off valves are doing it to make money on consumer ignorance. And it's working apparently.
Last edited by FourT6and2; 10-23-2017 at 04:49 PM.
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TriggrPullrUSMC (07-18-2022)
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TriggrPullrUSMC (07-18-2022)
10-23-2017, 04:59 PM
#25
Yeah, I'm a salty ******* for sure lol. Just seems strange that a dude is like Why? It's explained. He says "I'm not convinced. But again, why?" It's explained again. "Yeah, I'm not convinced..." Just going in circles. Believe it or not. Buy a fake BOV or not. Whatever.
