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What Boost Is R33 Ment To Sit At Idle

schnorky

By schnorky,
in Engines & Forced Induction

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schnorky Proficient

schnorky

Posted
Posted

hey guys and gurls

jst recently put a gfb bov on the r33 but didnt like it to much so took it off

but noticed that my stock boost guage was at -7 at idle now i put my stock bov on

and it sits a bit before-7 :s

cars still runing fine jst like it was before

turbo still excatly the same

could of it thrown out the boost gauge some how?

cheers guys

mosquitocoils Veteran

mosquitocoils

Posted
Posted

It'll be fine, just remember that you altered a part of the system that's supposed to stay pressurised.

The stock blow off valve is designed to leak a little bit when at idle, so I would suggest that changing from the GFB one (which wouldn't leak at idle) to the stock one would change your reading.

schnorky Proficient

schnorky

Posted
  • Author
Posted

Cheers guys I was worried at first but the car is still

mechanicly sound , cheers guys I'll check the vac line tomorrow if I was to change my bov

would I need to get a tune or somthing coz I was looking to buy the greddy type s

l_uk3y Proficient

l_uk3y

Posted
Posted
Cheers guys I was worried at first but the car is still

mechanicly sound , cheers guys I'll check the vac line tomorrow if I was to change my bov

would I need to get a tune or somthing coz I was looking to buy the greddy type s

Dont bother getting a tune if your only changing a BOV. If it is Recirculating back into the intake then nothing changes. If it is atmospheric then a tune wont really help unless you find an alternative to the factory Air Sensor (And even then you would only have to worry about the possible stalling issues caused by Atmo BOV's as covered in many, many a post before this)

Save the tune for big mods like injectors, turbos etc.

Luke

BezerkR32 Veteran

BezerkR32

Posted
Posted

ahhh ok. im sure nissan would have designed a vacuum leak into the intake system to aid smooth idle lol.

It'll be fine, just remember that you altered a part of the system that's supposed to stay pressurised.

The stock blow off valve is designed to leak a little bit when at idle, so I would suggest that changing from the GFB one (which wouldn't leak at idle) to the stock one would change your reading.

MBS206 Grand Master

MBS206

Posted
Posted
Even if the BOV is designed to leak, it's a NOT going to affect idle as the "leak" is not escaping outside of the air measured by the AFM.

I don't see, how at idle, the stock BOV is going to be "leaking".

Air flows from point of highest pressure to lowest. When idling, the WHOLE intake up until the throttle body is at the same pressure...

The vacuum point is from the throttle body to motor side... Nothing to do with before it...

gotRICE? Veteran

gotRICE?

Posted
Posted
I don't see, how at idle, the stock BOV is going to be "leaking".

Air flows from point of highest pressure to lowest. When idling, the WHOLE intake up until the throttle body is at the same pressure...

The vacuum point is from the throttle body to motor side... Nothing to do with before it...

Maybe it leaks backwards :blink:

doo doo Proficient

doo doo

Posted
Posted
I don't see, how at idle, the stock BOV is going to be "leaking".

Air flows from point of highest pressure to lowest. When idling, the WHOLE intake up until the throttle body is at the same pressure...

The vacuum point is from the throttle body to motor side... Nothing to do with before it...

Except for the fact there's a vacuum line (from after the throttles) to the top of the bov which would suck it open unless the spring held it shut. the factory spring tension is soft enough to allow a small leak at idle.

MBS206 Grand Master

MBS206

Posted
Posted
Except for the fact there's a vacuum line (from after the throttles) to the top of the bov which would suck it open unless the spring held it shut. the factory spring tension is soft enough to allow a small leak at idle.

Even if the bov were fully opened, pressure on the air filter side, and the IC pipe side is EQUAL, so there is no "leak".

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