Blow off Valve?
Thread Starter
Former Vendor of MBWorld
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From: South Florida
Fast Cars!
Originally posted by avlis
I don't think the "complaigning" (complaining) was about the thread being "boaring" (boring).
I don't think the "complaigning" (complaining) was about the thread being "boaring" (boring).
Senior Member
Joined: Apr 2002
Posts: 304
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From: san diego, ca
C230 kompressor C2 C7
are you sure this isn't a spelling B? i mean some of the questions people ask are just as elementary. like can i put a blow off valve on my blown engine? j/k dont' get all bent out of shape.
Super Member
Joined: Nov 2001
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From: San Diego
99' SLK 230 & 01' CLK 430
The reason all turbo car had "blow off valve" because the turbo are driven by exhaust gas. Factory install "blow off valve" to release the pressure everytime the throttle being close so there's no pressure build up to damages the turbo bearing in a long run but they are also doing it a way the does not create turbo lag by re-route the air back into the turbo. Most people used aftermarket "blow off valve" that released the air out side to create that PSSSSSSSSSSST sound. This create a little more turbo lad and make the engine to run a little richer.
On Supercharger car, you don't need "blow off valve" because the S/C is driven by belt. So everytime when the throttle is close during shifting, the engine (rpm) speed is slow down and so there's no pressure is being build up like turbo car. It may should cool but it actually does not help your engine in term of power gain.
On Supercharger car, you don't need "blow off valve" because the S/C is driven by belt. So everytime when the throttle is close during shifting, the engine (rpm) speed is slow down and so there's no pressure is being build up like turbo car. It may should cool but it actually does not help your engine in term of power gain.
Thread Starter
Former Vendor of MBWorld
Joined: Feb 2002
Posts: 12,403
Likes: 21
From: South Florida
Fast Cars!
Originally posted by linh
[B
On Supercharger car, you don't need "blow off valve" because the S/C is driven by belt. So everytime when the throttle is close during shifting, the engine (rpm) speed is slow down and so there's no pressure is being build up like turbo car. It may should cool but it actually does not help your engine in term of power gain. [/B]
[B
On Supercharger car, you don't need "blow off valve" because the S/C is driven by belt. So everytime when the throttle is close during shifting, the engine (rpm) speed is slow down and so there's no pressure is being build up like turbo car. It may should cool but it actually does not help your engine in term of power gain. [/B]
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From: Olympia, Washington
KLEEMANN C230K
Originally posted by vadim
Ok, let's make this thread a little more interesting...
If there is a bypass valve relieving excessive boost pressure (which was my understanding, too), then what is the point of installing a bigger crankshaft pulley? The idea is to create boost pressure higher than stock, but then the bypass valve will just stay open longer and kill it all!
Ok, let's make this thread a little more interesting...
If there is a bypass valve relieving excessive boost pressure (which was my understanding, too), then what is the point of installing a bigger crankshaft pulley? The idea is to create boost pressure higher than stock, but then the bypass valve will just stay open longer and kill it all!
The bypass valve works in the same manner as a blow-off valve (basically).
During "off pedal" it releases the excess pressure back into intake.
During "on pedal" it shuts, allowing all the boost into the intake.
It does not act like a wastegate, which is basically like the whistle in a teapot, allowing pressure to build to one point then allowing everything above that pressure to bleed out.
Hope this helps.
John.
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From: Ashburn, VA
'19 GLC 300, '19 TM3SR+
Originally posted by dj-po
The bypass valve works in the same manner as a blow-off valve (basically).
During "off pedal" it releases the excess pressure back into intake.
During "on pedal" it shuts, allowing all the boost into the intake.
It does not act like a wastegate, which is basically like the whistle in a teapot, allowing pressure to build to one point then allowing everything above that pressure to bleed out.
Hope this helps.
John.
The bypass valve works in the same manner as a blow-off valve (basically).
During "off pedal" it releases the excess pressure back into intake.
During "on pedal" it shuts, allowing all the boost into the intake.
It does not act like a wastegate, which is basically like the whistle in a teapot, allowing pressure to build to one point then allowing everything above that pressure to bleed out.
Hope this helps.
John.
Is the bypass valve triggered by a throttle position sensor or by a boost pressure sensor (if the latter exists)?
Also - are you sure this same bypass valve is not used to reduce overboost should it occur in other situations (such as using a larger crankshaft pulley)?
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From: Los Angeles
GL450, Sienna SE
If I get a supercharger Im getting a blow off valve. It doesnt really do much but I heard it works fine with superchargers. Its just not necessary. But like you I like the sound a lot. Intimidation factor. Hehe. Turns heads. 
If you are really curious I can ask my friend. He was telling me all about it the other day. PM me.
If you are really curious I can ask my friend. He was telling me all about it the other day. PM me.
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From: Olympia, Washington
KLEEMANN C230K
Originally posted by vadim
This makes sense, since the trottle shuts much quicker than the RPM drops in response to it, meaning there is a need to bleed this excessive pressure when you let off the gas.
Is the bypass valve triggered by a throttle position sensor or by a boost pressure sensor (if the latter exists)?
I'm not sure, but I'll check the manual
Also - are you sure this same bypass valve is not used to reduce overboost should it occur in other situations (such as using a larger crankshaft pulley)?
This makes sense, since the trottle shuts much quicker than the RPM drops in response to it, meaning there is a need to bleed this excessive pressure when you let off the gas.
Is the bypass valve triggered by a throttle position sensor or by a boost pressure sensor (if the latter exists)?
I'm not sure, but I'll check the manual
Also - are you sure this same bypass valve is not used to reduce overboost should it occur in other situations (such as using a larger crankshaft pulley)?
It hasn't done that to me, Luwin (D2Technik) has a boost gauge, and he doesn't see a drop in boost. So I would say no.
John.
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From: Santa Rosa, California
C230 sports Coupe
When you put a blow off valve on a supercharged car all it does is releave the pressure that is built up in the system in a different fashion than stock. The blow off valve will not remove the boost from the car because the car generates boost at such an alarming rate that it wouldnt make a difference wether you had a different type of release or not. BLOW OFF VALVES ARE OK FOR SUPERCHARGED CARS. to answer the initial question of this thread YES you can do it, NO it wont kill your powerband, if you tune your BOV right you can actually get a better power band.
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From: Abingdon, MD
Hysterical thread. Really! OMFG... I didn't post back then, only trolled. This was a blast to watch.
Fact is I need to look more into this as I am currently trying to redesign my instake system. A friend had built one, even used a tin can (NO *****) to cover the stock by-pass valve. Why Neal was given grief for calling the by-pass valve a blow-off valve, I don't know. I do not want to dump to the atmosphere though. Going to recirculate.
Fact is I need to look more into this as I am currently trying to redesign my instake system. A friend had built one, even used a tin can (NO *****) to cover the stock by-pass valve. Why Neal was given grief for calling the by-pass valve a blow-off valve, I don't know. I do not want to dump to the atmosphere though. Going to recirculate.
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Joined: Jan 2005
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From: Colorado
05-C230SC
I'll be cooler than all of you and put a BOV on my automatic. J/K
I like that dude's idea about painting a air-bottle blue & putting NOZ stickers on it, then setting it at AutoZone. We could even set it up so it releases pressure everytime you let off the gas. That's almost as cool as the hairdryers you can bolt to your intake that are battery powered... lol
I like that dude's idea about painting a air-bottle blue & putting NOZ stickers on it, then setting it at AutoZone. We could even set it up so it releases pressure everytime you let off the gas. That's almost as cool as the hairdryers you can bolt to your intake that are battery powered... lol
Out Of Control!
Joined: Nov 2001
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From: CA, NV, CO
Originally Posted by BlackC230Coupe
ahahahahahahaha, man i remeber this thread! its when i wanted to rice out my c230 stage! :p man i miss that car! 
This thread is older than you mang! 
:p So you still cosidering this BOV on your C55? 
:p
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From: Ashburn, VA
'19 GLC 300, '19 TM3SR+
Originally Posted by TurboChicken
When you put a blow off valve on a supercharged car all it does is releave the pressure that is built up in the system in a different fashion than stock. The blow off valve will not remove the boost from the car because the car generates boost at such an alarming rate that it wouldnt make a difference wether you had a different type of release or not. BLOW OFF VALVES ARE OK FOR SUPERCHARGED CARS. to answer the initial question of this thread YES you can do it, NO it wont kill your powerband, if you tune your BOV right you can actually get a better power band.
Last edited by vadim; Feb 1, 2005 at 11:54 PM.
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From: The blue white rock, third out.
2002 C230 Coupe(M111)
It almost warms my heart to read the snide remarks of the ledgendary Ebeneezer SoCal240/6 once again. I wonder where he is now...trolling the Hyundai boards?
