No disadvantage, unless you vent to atmosphere rather than back to the turbo inlet. Advantage is that you reduce the back pressure on the compressor wheel and a gasket or two, which helps the system last longer and spool better when it's spooling up. It's a good thing to have.

 

yup.. what he said if you vent to the atmosphere though your car will likely idle really bad and be severely rich between shifts

 

damn that answers some question... I am running rich.... so external BOV is actually only good for sound??

 

yup.. venting to the atmosphere only makes it louder..

 

Then why do almost all High HP cars seem to have open BOV's?
I thought there was more to gain off releasing to the atmosphere.
I guess I dont understand why. Please inform. :monkey:

 

Then why do almost all High HP cars seem to have open BOV's?
I thought there was more to gain off releasing to the atmosphere.
I guess I dont understand why. Please inform. :monkey:

Because it sounds cool and requires less piping. It's really just for the sounds though, the expel pressurized air at the same rate. Just FYI, the circulating BOVs are like my stock one.

It's the little actuator thing on the semi-right side. See how the pipes go from the pressurized IC pipes into the turbo inlet pipe. The BOV injects that "boosted" air into the "unboosted" side. This keeps the same volume of air in the system at all times. When you vent to the atmosphere there is no sensor to let the ECU know how much air you've lost, so it injects fuel based on the reading from the AFM or MAF or whatever, which is too high when you blow-off.

 

I thought BOV is a must have for turboed cars?

 

good topic...

 

Does cars that come with stock turbos have BOV? Since adding this will help life of engine and system, would it not make sense for them to add this to their vehicles so possibly less claim on warranty if they don't? If companies are doing this already which models have them? Can anyone list stock vehicles that comes with BOV or is it easier to list vehicles that don't have them or the year before BOV become standard equipment?

 

correct me if im wrong, i heard if your running a mas sensor then its a must to recirculate that sucka back into the inlet. if not it will throw off the a/f mixture thats already calculated, so not having it vent back and is still compensating for the air that should be recirculating is making it run rich. and depending on your car, idle will and wont be a problem. at least thats how it is for dsms.

i hear if you have mas you can eliminate it by getting a vpc or some kind of engine management, they are very $$$$, and if you use it just so you can vent to the atmosphere, then :thumbdown

but its hard just not to vent it

 

Does cars that come with stock turbos have BOV? Since adding this will help life of engine and system, would it not make sense for them to add this to their vehicles so possibly less claim on warranty? If companies are doing this already which models have them? Can anyone list stock vehicles that comes with BOV?

yup, dsms do. 1g, 2g. the reason the 2g guys change thier stock bov cause IT IS ISHT! it leaks and cant hold enough boost. the 1g bov is pretty good for stock and is sometimes a good enough upgrade for 2g guys. im sure a lot of other cars that have stock turbos come with bovs. i'm not sure which ones, so maybe others can enlighten us.

 

Does cars that come with stock turbos have BOV? Since adding this will help life of engine and system, would it not make sense for them to add this to their vehicles so possibly less claim on warranty if they don't? If companies are doing this already which models have them? Can anyone list stock vehicles that comes with BOV or is it easier to list vehicles that don't have them or the year before BOV become standard equipment?

That's what's in the picture I posted and pointed out. That is my stock BOV. I'm pretty sure every turbo factory car has a BOV, not having one is just stupid. All that compressed air has to go somewhere, and it isn't pretty when it tries to go out where it came in from. Exhaust it spining the turbine one way, then the surge trys to spin it the other way....not good. My car has an AFM and would run rich if I had an external BOV. Idle seems ok though. Last meet we installed an TurboXS Type-H BOV on an 87 turbo and the car idled fine. He has an auto so he doesn't have to deal with rich mixtures during acceleration because he never lets off the gas.

 

as you can tell I do not know too much about stock turbo cars, thanks for the answers looks like they all have them. I am now considering internal BOV, I am sick of the low idle and sometimes dies on me and I have to restart the car. Neways thanks for your input guys.
Maybe we should have some of these topics asked about each turbo parts until all major parts of turbo are answered, would be a great turbo-newbie thing.

 

I got a question for ya cool2miketlu. What did your shop do with your car's PCV system? This will be the pipes that come out of your valve cover(s).

And LarryD, what does your car do with it's PCV system? The mkIII Supra vents one side into the TB through a valve and the other straigt into the pre-turbo intake pipe. When I replaced the head gasket on the car I found quite a bit of oil lineing the intake pipes. I've checked the turbo and it's definately not coming from there, so all that's left is the PCV. Just curious on what else is out there to maybe get away from venting into the intake.

 

well I do not know, I am just a foo with money and a car walked in the shop

 

i believe 3rd gen RX-7s have a BOV, and my TP kit came w/ one as well, it comes with the Blitz SS. however I always thought there was an advantage to atmosphere venting, but I guess that is maybe a common misconception...

 

dont vent your bov into the atmosphere and it should fix your idle and stalling problems. that's how it is for dsms maybe its the same for yours since you are running mas, dont take my word though.

 

i dont know where my PCV went when it was stock.. been that long but im pretty sure it went from the valve cover back to the stock intake tube.. Ive since capped the intake tube and put a catch can breather filter on the line off the valve cover.

 

The orgasmic sound is definitely a plus!

 

well you can still hear a BOV when it vents back into the intake.. you can hear me coming with no problem.. its just louder when its vented to the atmosphere..

 

advantage: protect turbo
disadvantage: can't install misfiring sys