Jump to content
SAU Community

Slow Blitz Bov?


uk_skyman
 Share

Recommended Posts

My O.E.M. blow off valve started to leak after a t4 turbo install and 1.2 bar of AVCR boost , no wonder realy :(

Ive fitted a Blitz Blow off valve (to atmosphere) blanked off the recirc and removed the O.E.M valve.

Question.

Is the blitz valve supposed to be slower at reacting to the waste gate being closed?

Mine seems quite slow in comparison to the O.E.M one, as this when not atached to the recirc pipe, realy is an open/closed blow off, almost like a switch on or off.

This blitz is a bit slugish realy, ive wd40'd it and its all nice and smooth, this is making the blades in the turbo chop a bit, untill the valve is open and then its not fully open unless its realy getting some stick.

Any ideas, is this ok? normal?

Thanks Dean

Link to comment
Share on other sites

Hello mr skyman.I am running a blitz supersound bov with a backing plate blocking off the stock bov but have left the origional vaccum hoses running to the plenum for a more stock look.Ive never touched it and it comes on when boost is produced.

What i can tell you is the little adjustment nut on top of the bov will controll how tight the bov spring is,ie.It will be harder to open under the given pressure and will probably not be as quick to react to the lower rpm/boost.But if it were loose it will more than likely come on earlier on in the rpm/boost stage.This is more than likely your problem unless you have checked that when in that case then it may be that the bov itself is stuffed.

The wastegate has nothing to do with the bov's operation.The watsegate will open only to bypass excess exhaust pressure past the exhaust turbine.

Bov Operation Explained

When the compressor creates positive pressure,rushing all the air towards the plenum,the bov acts as a pressue relief valve for the system.

So when the butterfly slams shut and there is still positive pressure from the compressor being forced towards the plenum the bov relives the pipes of unwanted pressure.

And this is also why when the butterfly is open,there is air being rushed into the engine and the bov is opening without the butterfly being shut so as not to over force air into the engine,that the bov still should open without it being entirely closed reliving the system of what the engine cannot take.

Hope this helps...Dont fully quote me on this dude but i am pretty sure that my explanation is right.

Link to comment
Share on other sites

Thanks Chaps,

I've got the spring as loose as it can be, and it does lift a little when the gate is closed after light boosting and a little more when revved hard, so it seams to work ok, but im more worried about damaging my brand new turbo, the O.E.M valve even though it leaks is so fast at letting the pressure out that i get no flutter at all?? as you know they are just a spring and plunger inside and a few vac pipes off the top simplicity to the max so, just a few more squirts of wd40 to get it running smoother i guess.

Thanks again for the reasurance Dean

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share



  • Similar Content

  • Latest Posts

    • Unless there's something particular about the Greddy manifold's injector holes that I'm not aware of, those injetcors look to be totally wrong. They would absolutely want to be spaced up to get those long snouts out of the runner. Which, I think, is not usually the way that that problem is solved. I think the problem is solved by using the correct injectors, which would be much more like what Andrew posted.
    • Thanks for the reply, So i've continued playing around, and fitted the injector adaptors onto the injector, the fuel rail is not able to be mounted now as the injectors sit a bit further out. I suppose the point of the adaptors is so that the injector nozzle isn't so deep into the intake? I suppose 1mm extra on the o-ring would do it but still can't mount the rail onto the intake haha. Waiting on a reply from Aeroflow I'm sure there's something stupid that I'm missing...
    • EMJ33 or EJM33 - west end
    • I have a radium fuel rail on my Greddy manifold and used the supplied radium fuel injector to manifold adapters (The round green things pictured). I did always wonder if you could just go ahead and use the second lower hole like you're doing... Wouldn't thicker o-rings solve your issue?    
    • From what I've seen and experienced first hand with those powder extinguishers, they're good to use to break a window and escape the car, and half the time then do f**k all to stop a fire. You just need much more than 1KG worth of powder. Not to mention, half the time it's an engine bay fire, and you can't easily, and do not want to completely open the bonnet, so you're left pretending to be an American Infantry... Spray and Pray baby!   And then 100% that shit is really destructive afterwards!   Realistically, those little ones at a race track might help you keep the fire from growing and give the fire marshal / truck a chance to actually get to you with their multiple large bottles.   For a road car, these days, prepare to deboard as quickly as humanly possible, and move to safety. Allow insurance to fix replace it (unless it's like a rare classic etc, then do nearly everything possible to save it!) Keep the little extinguisher with you to help protect other things around you from burning while you stand there singing "How can we sleep while our beds are burning?"   Secondly, powder extinguishers I freaking hate for indoor use, (this isn't really relevant to a car) as you will get a powder fog around you, and it can be disorientating.   When I did fire training when at BlueScope Steel, they have (had?) their own fire brigade on site. We did all the training, and at the end we were told, "If it's an indoor fire, and you need to use a powder extinguisher, we as the fire brigade would rather you just exit the building, you're more likely to get lost in the smoke and powder fog than do much help, so just GTFO" And pretty much that was what they said for most other fires too, grab extinguisher, if it's much more than paper in a bin fire, use extinguisher to get you and others out of the building to safety...   Part of me wishes when my Skyline caught alight many moons ago, I let insurance sort it out, instead of putting the fire out... part of me now says "But I've saved a classic before it was a classic!"
×
×
  • Create New...