OK.. Why can't we use a BOV
08-05-2002, 03:27 PM
#1
New Member
Thread Starter
Join Date: Apr 2002
Posts: 443
Likes: 0
Received 0 Likes
on
0 Posts
OK.. Why can't we use a BOV
OK I admit, I dont care about the performance increase with a BOV, I love the sound. I am sure that there is some reason why the BOV is better for turbos. Or worse... I dont care. LOL I just want to know why it is that we "Can't use a BOV". I mean is it hard on our turbos? Is there a reason why Audi does not use a BOV? What is the benifit to using a DV vs BOV? All I ever here is that the DV fail... and that BOV rock. Please I need an answer..... I want the sound without having to press my lips togeather, build up pressure behind them and let it out "PSSSSSSSSHHHH!!!" every time I shift! LOL please your advise is appriciated!
08-05-2002, 03:32 PM
#2
Junior Member
Join Date: Sep 2001
Posts: 1,408
Likes: 0
Received 0 Likes
on
0 Posts
it is a matter of how much air the ECU thinks it is getting-->
BOVs and DVs sit between the intake and the turbo. when a DV diverts incoming air, the air bypasses the turbo but continues to the intake manifold. when a BOV blows-off air, the air is lost to the atmosphere. since our car has a MAF that determines the amount of air the car is receiving, using a BOV means the measure amount of air is NOT reaching the combustion chamber.
is this critical? not really. BOV/DVs actuate when you loose boost, so you are either letting of the gas anyway, or shifting. is it bad for your car? i dont know. i'm sure somebody who has had bad experiences will chime in here. what would i do? despite wanting the HKS SSQ over the Greddy Type-S (converted to a DV), I'm still sticking wth the DV setup. just my humble opinion.
is this critical? not really. BOV/DVs actuate when you loose boost, so you are either letting of the gas anyway, or shifting. is it bad for your car? i dont know. i'm sure somebody who has had bad experiences will chime in here. what would i do? despite wanting the HKS SSQ over the Greddy Type-S (converted to a DV), I'm still sticking wth the DV setup. just my humble opinion.
08-05-2002, 03:45 PM
#3
Member
Join Date: May 2002
Posts: 15,536
Likes: 0
Received 0 Likes
on
0 Posts
there are a number of posts about it, actually...
i just made one a few days ago...
search for bov and dv and a lot of information will come up... or search for my 'kicking a dead horse' thread, and you should find the answers you need.
basically, it's a closed system with the dv, and an open one with the bov. some feel that the open system upsets the way the motor was engineered... ultimately, it's your call.
search for bov and dv and a lot of information will come up... or search for my 'kicking a dead horse' thread, and you should find the answers you need.
basically, it's a closed system with the dv, and an open one with the bov. some feel that the open system upsets the way the motor was engineered... ultimately, it's your call.
08-05-2002, 04:14 PM
#5
AudiWorld Super User
Join Date: Mar 2000
Location: Geneva, Illinois
Posts: 6,555
Likes: 0
Received 0 Likes
on
0 Posts
If you install a Blow-Off valve in the Bosch Motronic system....
The venting of metered all will cause what Bosch calls a "false air" condition and cause the car to run rich (possibly very rich) causing a propable loss of power and possible fouling of spark plugs and further long term damage (cat converter).
I've experience this situation with my supercharger on my A4. I located a manual on the operation of the Motronic system and it talks specifically about this situation. You definately don't want to blow off all that metered air to the atmosphere, unless you have a way to meter it on the way out and communicate that to the ECU. Even a leak in a vacuum line can cause "false air" condition and lead to rich/lean operation.
Believe it or not.
I've experience this situation with my supercharger on my A4. I located a manual on the operation of the Motronic system and it talks specifically about this situation. You definately don't want to blow off all that metered air to the atmosphere, unless you have a way to meter it on the way out and communicate that to the ECU. Even a leak in a vacuum line can cause "false air" condition and lead to rich/lean operation.
Believe it or not.
08-05-2002, 04:15 PM
#6
New Member
Thread Starter
Join Date: Apr 2002
Posts: 443
Likes: 0
Received 0 Likes
on
0 Posts
Re: OK..tell me what you think a BOV does and a DV does..and lets start there with this discussion..
Well it is my understanding that the BOV lets the pressure out of the system keeping the turbo spinning. The DV sends that excess pressure back into the system stopping the Turbo itself. I really dont know what benifit/damage either of them do. I just want to know if I can or even should put a BOV on my TT?!
08-05-2002, 04:22 PM
#7
AudiWorld Super User
Join Date: Sep 2001
Location: Manhattan, NY
Posts: 11,257
Likes: 0
Received 0 Likes
on
0 Posts
You'll "blow up your engine".. lol
Sorry.. couldn't help myself.. and no you won't, as far as I know of there is no documented case of a 1.8T from a vw or Audi blowing up b.c of a BOV.. As for which one to buy Im eying up the ecs valve.. Ive heard good things and have heard of someone vag testing the car to make sure it wasn't running rich.. It does hold boost better, and Im wondering if it has to be serviced like the DVs..<ul><li><a href="https://forums.audiworld.com/tt/msgs/642981.phtml">https://forums.audiworld.com/tt/msgs/642981.phtml</a</li></ul>
Trending Topics
08-05-2002, 04:24 PM
#8
AudiWorld Super User
Join Date: Sep 2001
Location: Manhattan, NY
Posts: 11,257
Likes: 0
Received 0 Likes
on
0 Posts
I believe the ecs BOV has the option of redirecting air back to the intake system
Thats my only reason for even considering it.. If it does it correctly and people have documented that the car is not running rich, then perfect.. right?
