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Does this have any performance impact at all decrease/increase or is it just for the sound
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.
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=-
Thanks for all that info. I like many others I'm sure were in the belief that there would be no negative effects on performance. I thought it was just an acoustic add on.
I have Weistec VTA adaptor installed on my C450 AMG = Yes, you need two but when you purchase from them, they send you two.
First off, the left side turbo is NOT easy to get to so that you can install the VTA adaptor. The right side turbo is easy to install the VTA adaptor on your own. I took my car to Eurocharge to install the second VTA adaptor as I didn't have the patients and it was to cold to stand and do it. They were great and it took them around 1 hour to install the left VTA adaptor on to the turbo.
Forward Video to 12min or so if you don't want to hear me speak about my upgrades.
PS - This does not increase your performance in anyway. It's clearly for sound.
Does this have any performance impact at all decrease/increase or is it just for the sound
just sound..
a GFB DV+ does give improved performance.. ie maintains boost between shifts making boost build a little quicker... the characteristic is good at smoothing shifts particularly on DCT's.. but holds boost up on the 7g and 9g auto's too...
Was anybody actually able to do any sort of verification if these BOV or VTA valves have any effect on performance at all? Minimal increase or minimal decrease?
I understand the sound aspect, and thats what everyone here wants when being interested in this specific mod.
Was anybody actually able to do any sort of verification if these BOV or VTA valves have any effect on performance at all? Minimal increase or minimal decrease?
I understand the sound aspect, and thats what everyone here wants when being interested in this specific mod.
yeah thats right, only thing you get out of this mod is a nice little whoosh sound when the pressured air releases. its deffinitely beneficial for the overall lifespan of the turbo. all that pressure now has somewhere to be released instead of remaining built up in the turbo
Hi mate. Loved your post. I checked their website but it's difficult to make sure. Will this work on the 2019 E200 coupe? Your engine looks fairly similar but I want to make sure before I bite the bullet. Thanks
Do you just put the BOV over after unscrewing or Do I need to remove the existing valve? Just want to make sure before buying, Thanks!
Our spacer goes between the OE bypass valve and the compressor housing of the turbo. Check the pics at the beginning of the thread, shows how easy it is to install
Don’t listen to this guy. There’s ZERO negative effects by adding blow off valve spacers to your car. They’re diverted valves anyway, not priority valves and the spacers they make for them are for acoustics. Purchase away my man. It’s not gonna steal any power whatsoever.
Originally Posted by lobe50
Thanks for all that info. I like many others I'm sure were in the belief that there would be no negative effects on performance. I thought it was just an acoustic add on.
I just installed the Burger Tuning BOV spacers on my 2021 C43 last night. It was a PITA but they're both in. The car sounds great...it's nowhere near as loud and obnoxious as the WRX drivers.
Thanks for all that info. I like many others I'm sure were in the belief that there would be no negative effects on performance. I thought it was just an acoustic add on.
His long winded and waste of time response is what is total nonsense lol. And not to be attacking his “opinion” and “misleading and wrong information” or him, it’s just not correct info.
Instead of forcing the air back into the turbo to be recycled and THEN CREATING TURBO LAG, it releases the air into the atmosphere so it isn’t forced back into turbo. If most Mercedes owners were sound snobs and worried about what other people think, they would be installed from the factory. As they don’t create anymore power, they do however create better performance in your shifting and turbo boost. I have them installed and I notice a big difference. It’s only $150-$200 (depending on where you get them) to try them out for yourself. If you don’t like the sound they make, sell them. Keep in mind that if they harmed your engine or didn’t work, all of these big companies that all of the haters buy their tuners and exhaust systems from wouldn’t make them for the simple fact that they would get a lot of bad press from them. It’s simple common sense. So.. at the end of the day, the companies that make these things are professionals and it’s obvious that some of the people on here definitely aren’t lol. Besides.. who cares what anyone thinks? As long as it puts a smile on your face, that’s all that matters. I have a C450, C63, and a AMG GT and they’re on all of them.
Does anybody have the install photos or video of how to install a passenger side blow off valve spacer on a C43/c450 3.0L TwinTurbo? somebody told me The passenger side turbo was upside down? I do t see from just looking under the hood. And there isn’t much on youtube worth watching. There’s an Asian chick trying to show us how to, but she was lost too. They sound great and I feel a difference in my shifts with just one so far
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