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New Bov Causes Unlimited Boost?

skeg_man

By skeg_man,
in Victoria

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skeg_man Enthusiast

skeg_man

Posted
Posted

Hey All,

Just recently got and installed a Greddy (REAL branded not fake) Type S bov (Plumb back). After the install I went for a quick spin to test for the "fluttering" to see if I had to adjust the top bolt. I then noticed how "fast" and quick it was pulling. I was getting up into 15-18psi. I have an upgraded turbo, not the factory installed so I wasn't too stressed but kept off the WOT till I got home. I adjusted my MBC which is a TurboTech so it would be on low boost (previously set at around 13psi for my recent tune). Went for another spin, still no luck. Just hits the high boost and looks like it'll keep going.

I have since then, put the stock one back on and its all back to normal... Only getting up to 8psi of boost.

Does anyone have any thoughts? or had one previously installed to shed some light? Also if I've left anything out, let me know.

Sorry for the story, thanks for reading.

Cheers

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paulr33 Grand Master

paulr33

Posted
Posted

the only thing that causes unlimited boost is the actuator not opening

this occurs if the actuator has no boost signal

ie the vac line is blocked, leads no where or has no manifold pressure signal

a broken BOV, a blocked BOV or a faulty BOV has no capacity to cause unlimited boost

skeg_man Enthusiast

skeg_man

Posted
  • Author
Posted

Thanks for the fast reply Paul. I thought it may have been one of my vac lines but I checked all them out. Not to mention when I put the stock BOV back on, no problems. Went back to normal. Maybe I'll double check everything tomoz after work. Thanks for the input mate.

mark33gtst Community Regular

mark33gtst

Posted
Posted

Did you modify your stock bov to make it flutter before? I have seen people block the hose between the manifold and bov to make it flutter.. Only problem is it creates a boost leak, lack in response etc. So if you put a new properly set up bov it would increase response/boost etc...

Munkyb0y Grand Master

Munkyb0y

Posted
Posted

where is your turbotech getting it's pressure feed from? some people tee off the bov vaccum hose. not a smart way to do it. but if you have removed this feed to the turbotech somehow along the way, that would also cause unlimited boost.

skeg_man Enthusiast

skeg_man

Posted
  • Author
Posted (edited)

Cheers for the replies guys. I never had my stock one set for "flutter". It was always and still is re-circ. I've just checked my turbotech boost controller and the bottom line that is suppose to be pressure seem to be vac. I removed the pipe while the car was running and its "sucking" the air. So thats "VAC" yeh? The feed came from the carbon canister (thicker line).

I've now put the bottom line to the turbo housing, which has a outlet that was first joined to the actuator when I first got the new turbo. I assume that this will be an good "pressured" source?

Please let me know if i've done anything spastic? Also why wouldn't the turbo be unlimited with the the stock BOV? Would it be because it leaks at a certain PSI?

Cheers for the help guys.

rolleyes.gif

Edited by skeg_man
Munkyb0y Grand Master

Munkyb0y

Posted
Posted

yeah the line off the turbo is a good one for the feed to the mbc. with the turbotech, pressure goes in to the straight end, and the nipple coming off the side goes to the actuator.

there shouldnt be any difference in boost levels between two working bovs, but if your stock one was absolutley stuffed, maybe. it would have to have been basically totally open all the time and recircing pressure back into the system under boost. i guess it's possible.

skeg_man Enthusiast

skeg_man

Posted
  • Author
Posted

Cool cool. It always seem to work. Like releasing the pressure making the "swoosh" sound. Who knows.

Was the line i was talking about a "VAC" line? the one from the carbon canister?

Cheers again for the help.

  • 2 weeks later...
Munkyb0y Grand Master

Munkyb0y

Posted
Posted

sorry dude, i just saw your PM. i have replied in detail.

it looks like you were using the turbotech, and still had your stock solenoid hooked up as well. you need to disconnect your solenoid.

test your actuator on it's own, then if that works ok, hook up the turbotech, and hopefully it will all be good.

it's all explained in the PM

skeg_man Enthusiast

skeg_man

Posted
  • Author
Posted

@ Adzmx - Unsure what you mean mate?

Anyways, found out that I had a faulty actuator. So now i've upgraded to a HKS. Waiting for it to come. So i'll keep everyone posted. Anyone want to buy a BOV? lol.

Cheers again all.

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