Turbo Blowoff/bypass Valves
Thread Starter
Junior Member
Joined: Oct 2007
Posts: 62
Likes: 14
From: Philadelphia, PA
2014 E550 4Matic
Turbo Blowoff/bypass Valves
So from I've found, Victory Road Performance, Renntech, and Weistec all offer a blowoff valve modification. Any real advantage/disadvantage to a specific one? If they all work well, then I guess it doesn't matter?
Super Member
Joined: Feb 2018
Posts: 604
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From: Houston Tx
2014 AMG E63S and 2020 AMG GTC
some of the systems operate off a solenoid and the MAP sensor, while the cheaper unit work off a spring in tension within the valve...
They all get across the finish line more or less in a similar fashion by venting pressure at throttle lift off and during gear changes. I'm not sure if one reacts faster than the other.
They all get across the finish line more or less in a similar fashion by venting pressure at throttle lift off and during gear changes. I'm not sure if one reacts faster than the other.
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Joined: Aug 2003
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From: In my garage
E55, GLS450, GL63, GLE350
Typically a BOV works off engine vacuum but there are electronic ones too. The ones I've seen from Renntech and Weistec and ones I've used on other vehicles are operated off engine vacuum. There is a nipple underneath the throttle body where you pull vacuum. When the throttle is closed it creates a vacuum and the vacuum activates the opening of the BOV.
A POV or pop off valve is pressure activated and has a spring, many are adjustable, to a predetermined setting to release any pressure above the set level to protect from too much boost or compressor surge.
Both of these are meant to help save the turbo from the backward moving shockwave from the throttle closing. Typically manufacturers us a recirculation valve to loop the air back to the turbo. The recirc BOV is more quiet than releasing to the atmosphere.
A POV or pop off valve is pressure activated and has a spring, many are adjustable, to a predetermined setting to release any pressure above the set level to protect from too much boost or compressor surge.
Both of these are meant to help save the turbo from the backward moving shockwave from the throttle closing. Typically manufacturers us a recirculation valve to loop the air back to the turbo. The recirc BOV is more quiet than releasing to the atmosphere.
Thread Starter
Junior Member
Joined: Oct 2007
Posts: 62
Likes: 14
From: Philadelphia, PA
2014 E550 4Matic
Typically a BOV works off engine vacuum but there are electronic ones too. The ones I've seen from Renntech and Weistec and ones I've used on other vehicles are operated off engine vacuum. There is a nipple underneath the throttle body where you pull vacuum. When the throttle is closed it creates a vacuum and the vacuum activates the opening of the BOV.
A POV or pop off valve is pressure activated and has a spring, many are adjustable, to a predetermined setting to release any pressure above the set level to protect from too much boost or compressor surge.
Both of these are meant to help save the turbo from the backward moving shockwave from the throttle closing. Typically manufacturers us a recirculation valve to loop the air back to the turbo. The recirc BOV is more quiet than releasing to the atmosphere.
A POV or pop off valve is pressure activated and has a spring, many are adjustable, to a predetermined setting to release any pressure above the set level to protect from too much boost or compressor surge.
Both of these are meant to help save the turbo from the backward moving shockwave from the throttle closing. Typically manufacturers us a recirculation valve to loop the air back to the turbo. The recirc BOV is more quiet than releasing to the atmosphere.
Member
Joined: Oct 2019
Posts: 155
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E63S
Sometimes the air is recirculated back in front of the turbo(s) to help with transient throttle inputs.
Isn't the Mercedes system not actually shutting the throttle completely anyways, so an aftermarket BOV isn't "saving the turbos", as much as "making more noise"....
