# BOV on VR6 24v turbo?



## Sekely321 (Sep 25, 2009)

I just got the C2 1+ kit installed on my 03 VR6 24v. i asked the guys at C2 if i could put a BOV on and thy said no cause VW's can't tell how much air is released from the BOV therefore making the car sputter and stall. So, i looked on here (as i always do







) for some advice and answers. I saw on a post that another guy with a VR6T had a BOV. Whats the deal?







Thanks and i can't wait to hear some results.


----------



## MeiK (Mar 18, 2005)

*Re: BOV on VR6 24v turbo? (Sekely321)*

You think the idiots on the Vortex know better than Jeff & the guys at C2?








Basically you just want someone to tell you that you can use a cheesy open-air blow off valve on your VW.







Don't do it. Mainly because it's cheesy - secondly because it won't work with most tunes. Guys who DO have an open BOV usually run standalone or a MAFless tune.
edit: If your car running yet? You can clearly hear the DV on a C2 car with that 'batwing' turbo inlet pipe...
edit again: I made this image 3 years ago for 1.8T fanbois who were (and still are) obsessed with running stupid open blow off valves:
http://i15.photobucket.com/alb...s.jpg


_Modified by MeiK at 9:32 AM 2-13-2010_


----------



## 24valvedGTI (Jan 27, 2007)

*Re: BOV on VR6 24v turbo? (MeiK)*

Trust me a vrt will be loud enough. No need to run an open blow off valve. If you feel the need to run an open blow off og and buy a honda or an srt-4


----------



## blklbl540 (Jun 14, 2006)

*Re: BOV on VR6 24v turbo? (24valvedGTI)*


_Quote, originally posted by *24valvedGTI* »_Trust me a vrt will be loud enough.


x2... if you want people to know you have a turbo (which is pretty ghey anyway), a VRT is pretty unmistakable. Plus, DVs are just loud enough. BOVs get REALLY annoying after the first three times you hear it.


----------



## DannyLo (Aug 2, 2006)

*Re: BOV on VR6 24v turbo? (blklbl540)*

if you're so determined to run an actual BOV...
...just get a greddy type RS with 1" adapters and recirculate it like a DV.
Otherwise just get a DV...It's cheaper and does the job the way the system was designed to do it.
If you really really really want atmospheric dump, you should ask the guys at C2 if the Splitter from forge would work with their tune. (Recirculates 70% and dumps 30%)
That's really it for choices:
Recirculated BOV
DV
Splitter/dualport type DV (if the tune can run with it)
Good luck


----------



## PhReE (Sep 16, 2004)

*Re: BOV on VR6 24v turbo? (Sekely321)*

I run a 50mm Tial BOV, and there's also a local turbo R32 with a tial Q, and plenty of BT 1.8T's running tial valves also. Believe it or not the car really doesn't run much differently because generally you are coasting 'off the gas' when the bov is open, which makes the engine shut the injectors off anyways, so at the time you are 'messing up' the air calculations, you're usually not injecting fuel so it doesn't matter as much as many people make it out to be. Why am I running a bov? well the kit had this setup on it when I bought it, if I built it from scratch I probably would do a DV. However, this setup actually runs pretty good, now there are two things to note, the Tial BOV is the only bov to use, it's the only one that flows nearly enough for a turbo the size of the ones on VR6's (and frankly mine doesn't even flow enough, I'd suggest the Q) and also make sure to have the spring set right so it doesn't hang open at idle or it WILL run like ****.


----------



## Sekely321 (Sep 25, 2009)

*Re: BOV on VR6 24v turbo? (MeiK)*

I am a rookie to the whole turbo thing. Advice from anywhere is greatly appreciated. I do very much trust the guys at C2, and i have read alot of posts on here from people that seem to be very knowledgable. I didn't plan on running a BOV on my car, i just wanted to understand why some people run with them and others dont and if there were any benefits. Thank you everyone for helping me out. Like i said, i am a rookie and want to learn everything about this application. I want to do this right the first time and not just dive in and blow my engine or something. 

_Modified by Sekely321 at 10:22 AM 2-13-2010_


_Modified by Sekely321 at 10:42 AM 2-13-2010_


----------



## PhReE (Sep 16, 2004)

*Re: BOV on VR6 24v turbo? (Sekely321)*

No benefits http://****************.com/smile/emthup.gif (well, the install is a bit simpler if it's a custom kit)


----------



## mr.candid (Sep 11, 2008)

i run a 50mm Tial BOV with a gt35 turbo, it works very well. I feel as i depends really on your build


----------



## 24valvedGTI (Jan 27, 2007)

*Re: (mr.candid)*









Is mine big enough????? It is recirculated


----------



## Snitches Get Stitches (Jul 21, 2007)

GAWDZILLA!! The biggest DV evar.....I am ging to run the same DV...moves a huge amount of air.....thinking about welding it onto my equally gigantic intercooler(awic)...very little room for the turbo inlet pipe..any idea if C2 will sell just their BAT Turbo inlet pipe? I have the MAF and filter, but was thinking this can simplify my already complicated build..
sorry to threadjack, but if C2 says to use a DV?BOV recirc'd, why dont you follow their advice, as they wrote the programing and therefore get to tell you what works!!


----------



## dubdoor (Apr 23, 2006)

*Re: (Snitches Get Stitches)*

tial alpha Q makes quite a racket when re-routing 15+psi....


----------



## MeiK (Mar 18, 2005)

*Re: BOV on VR6 24v turbo? (PhReE)*


_Quote, originally posted by *PhReE* »_I run a 50mm Tial BOV, and there's also a local turbo R32 with a tial Q, and plenty of BT 1.8T's running tial valves also. Believe it or not the car really doesn't run much differently because generally you are coasting 'off the gas' when the bov is open, which makes the engine shut the injectors off anyways, so at the time you are 'messing up' the air calculations, 

Unitronic offers a mafless tune. If you bought it like that and it runs correctly - chances are it's tuned for it. Many, many 1.8T tunes are mafless (strictly MAP), and that .:R32 owner may also be running a mafless tune or standalone. I wouldn't tell anyone "it won't run much differently" without rerouting into the intake. Especially on a kit that's MEANT for it. 
How about this - anyone with a C2 kit... Run your car with the DV open as an experiment. I bet it'll sputter out and stall between gears.







Have your VAG-COM ready to clear the improper air reading code. 

_Quote, originally posted by *Sekely321* »_I am a rookie to the whole turbo thing. Advice from anywhere is greatly appreciated. I do very much trust the guys at C2, and i have read alot of posts on here from people that seem to be very knowledgable. I didn't plan on running a BOV on my car, i just wanted to understand why some people run with them and others dont and if there were any benefits. Thank you everyone for helping me out. Like i said, i am a rookie and want to learn everything about this application. I want to do this right the first time and not just dive in and blow my engine or something. 

If everyone had that attitude when starting out - the vortex would be a better place!















edit: To clairify - nothing wrong at all with running a rerouted BOV... Which is essentially a DV. I'd be a hypocrite:

__
Image uploading. Refresh page to view











_Modified by MeiK at 8:42 PM 2-13-2010_


----------



## 24valvedGTI (Jan 27, 2007)

*Re: BOV on VR6 24v turbo? (MeiK)*

Off topic but MEIK your car still makes my jaw drop http://****************.com/smile/emthup.gif http://****************.com/smile/emthup.gif http://****************.com/smile/emthup.gif


----------



## One Gray GLI (Apr 2, 2007)

*Re: BOV on VR6 24v turbo? (Lieutenant Dan)*


_Quote, originally posted by *Lieutenant Dan* »_if you're so determined to run an actual BOV...
...just get a greddy type RS with 1" adapters and recirculate it like a DV.


guess I can put a little advertisement here.
I have one, you just need to buy the adapter from ATP.







Or buy my whole intercooler pipe if you have stock intake manifold.


----------



## PhReE (Sep 16, 2004)

*Re: BOV on VR6 24v turbo? (MeiK)*


_Quote, originally posted by *MeiK* »_
Unitronic offers a mafless tune. If you bought it like that and it runs correctly - chances are it's tuned for it. Many, many 1.8T tunes are mafless (strictly MAP), and that .:R32 owner may also be running a mafless tune or standalone. I wouldn't tell anyone "it won't run much differently" without rerouting into the intake. Especially on a kit that's MEANT for it. 

VR6's don't have MAPs and thus there are no MAF-less tunes for VRT's. My car, along with the Turbo R I was talking about, are both using the Uni 630cc file which uses the Audi A8 MAF housing. http://****************.com/smile/emthup.gif


----------



## MeiK (Mar 18, 2005)

*Re: BOV on VR6 24v turbo? (PhReE)*


_Quote, originally posted by *PhReE* »_VR6's don't have MAPs and thus there are no MAF-less tunes for VRT's.

Unitronic only recently stopped offering the MAFless files. They absolutely do (or at least DID) exist.








Jeff Atwood in response to MAFless files on VR6s:

_Quote »_I won't make a MAF-less file. Can it be done: sure.
ANY/ALL MAF-less files are running use a substitute (modeled) air flow. Same as if you unplug the maf on a stock car, except missing maf errors are hidden.
If you unplugged the main load sensor on a standalone ecu, the engine simply would not run.
Thoughts:
How exactly does a mafless file measure the airflow difference between two different set-ups? Answer: it cannot.
Example:
Total flow and thus power on a 10 psi boost on a Gt42r 4" exhaust car is way different than a say a Vortech blower at 10-12psi on a stock exhaust car. The same MAF based tune will run BOTH cars well.
On Big turbo 1.8T cars I change the MAP and MAF such that ecu can runs 'like stock' and maintains full boost control, to 30 or 45 psi boost....
If you don't need boost control beyond the stock MAP limit, thats fine, no new needed MAP sensor. Stock ecu only uses MAP for boost control and load substitution when maf is missing.
It all comes down to philosophy:
I make software that I believe follows the original ecu's 'philosphy'.
Removing the MAIN LOAD measuring sensor does not follow how the ecu delivers fuel and controls ignition.

Regardless - a C2 kitted car would likely run like balls with an open BOV.







I tried it for ****s on my car (running a C2 tune) and it stalled out pretty quick. 


_Modified by MeiK at 12:40 PM 2-15-2010_


----------



## PhReE (Sep 16, 2004)

*Re: BOV on VR6 24v turbo? (MeiK)*

Yeah seems like that bit is actually talking more about the 1.8T's running mafless. As he says, you need something to model airflow, and if you take away the MAF, then you need something else. On a VR6 all you are left with is wideband o2, which is more of a reactionary control system than a proactive control system, and I wouldn't think it's safe to depend on that alone to fuel a motor. On a 1.8T, they have the MAP, which along with intake temp you can use to model the data that the MAF provides, thus making the MAF itself somewhat redundant. We aren't blessed with that level of redundancy out of the box. I have never heard of or seen a VR6 turbo car designed to run MAF-less, at least using the OE ECU. Uni still does offer mafless 1.8T files, I do know of plenty of local 1.8T guys running mafless tunes. They simply have more sensors which make it possible (even if some people don't agree with the philosophy, which is fine). http://****************.com/smile/emthup.gif


----------



## MeiK (Mar 18, 2005)

*Re: BOV on VR6 24v turbo? (PhReE)*

^^^ That quote was taken from an .:R32 thread talking about VR6s running a MAFless tune specifically. http://****************.com/smile/emthup.gif 
edit: I agree with you btw - MAFless tunes aren't a great idea for cars without a MAP sensor. That's probably why UNI stopped selling 'em.










_Modified by MeiK at 1:08 PM 2-15-2010_


----------



## PhReE (Sep 16, 2004)

*Re: BOV on VR6 24v turbo? (MeiK)*


_Quote, originally posted by *MeiK* »_^^^ That quote was taken from an .:R32 thread talking about VR6s running a MAFless tune specifically. http://****************.com/smile/emthup.gif 
edit: I agree with you btw - MAFless tunes aren't a great idea for cars without a MAP sensor. That's probably why UNI stopped selling 'em.









_Modified by MeiK at 1:08 PM 2-15-2010_

So, Uni REALLY sold mafless VR6 tunes? That's pretty scary.. thinking about how it would have to work...


----------



## mr.candid (Sep 11, 2008)

who else runs MAFless on a aftermarket ems


----------



## MeiK (Mar 18, 2005)

*Re: BOV on VR6 24v turbo? (PhReE)*


_Quote, originally posted by *PhReE* »_
So, Uni REALLY sold mafless VR6 tunes? That's pretty scary.. thinking about how it would have to work... 

Weird, right? 
Makes for a good read: (not that it matters now since they discontinued the MAFless files)
http://forums.motivemag.com/ze...age=4
I don't think the ECU reads from the MAF under wide open throttle, anyways so it's all partial throttle stuff that would have to be different for a MAFless tune. Ahhh what do I know.







Maybe Jeff @ C2 will see this and chime in. http://****************.com/smile/emthup.gif


----------



## masterqaz (Oct 5, 2007)

does it not call for a map sensor to be installed. That would be the smart way to properly map out air density. Much more effective than a maf.


----------



## VeeAreSex (Mar 18, 2009)

*Re: (masterqaz)*

Like many said before - VRT will be loud enough, especially with an external dump. You CAN run a BOV and the car will drive fine - once you get used to how operate it. If you are under boost and clutch-in followed by no throttle, the MAF will freak out due to no more airflow and a stall will result. All you need to do is let the clutch back out and the motor will restart. OR when you clutch in, don't clutch all the way in and tap the throttle a bit before you push the clutch to the floor. DVs or better for dubs but to it's your car and your money so you have to live with it.


----------



## DannyLo (Aug 2, 2006)

*Re: (VeeAreSex)*

i got a baileys motorsport DV on my car and it's still audible, unless the dump opens...then it's just the sound of my car trying to eat everything in its path


----------



## MeiK (Mar 18, 2005)

*Re: (VeeAreSex)*


_Quote, originally posted by *VeeAreSex* »_You CAN run a BOV and the car will drive fine - once you get used to how operate it. If you are under boost and clutch-in followed by no throttle, the MAF will freak out due to no more airflow and a stall will result. All you need to do is let the clutch back out and the motor will restart. OR when you clutch in, don't clutch all the way in and tap the throttle a bit before you push the clutch to the floor. DVs or better for dubs but to it's your car and your money so you have to live with it. 

You consider that "driving fine"? And on my C2 programming - it will NOT idle correctly with an open BOV. I only tested to prove a point - not because I was considering it.


----------

