Blocking Off Bov

[CRoNic...]

Yeah I know mate, it's crazy! I have the 95/98 debate all the time with my mums partner. He thinks he knows everything about anything and says "98 is just like 95"...

It's just.... stupid. But yes, some people do still believe/say/recommend this to others!!

[craig R33]

lol @ 3 pages of bs in one day!

if your that concerned, ring a few workshops ffs,

or, use the search function, this topic has been covered countless times in the forced induction section.

[Damo_R34]

if youve read those countless threads, why dont you tell us the answer Craig

[craig R33]

it does no f**king damage!

listen to all the people that have actually done it, rather than those who think they know everything.

if your running 14 psi on a stock turbo with no bov, EXPECT the kent to blow a blade sooner or later!

i for one, ran 14 psi, on my hi flow vg30 for yonks, not a prob.

there are plenty of others out there who have the some opinion, joel for one.

f**k me.

[R32 project]

i have blocked boV on my r32 running 12 psi, no problems and i see no logical reason why it would cause damage to the turbo!

[Damo_R34]

lol, sandy gina?

Well im shoving 12.5 psi into my stock un-hi flowed R34 turbs so ill let you know how i go.

Edited October 21, 2008 by Damo_R34

[Krishy]

it does no f**king damage!

listen to all the people that have actually done it, rather than those who think they know everything.

if your running 14 psi on a stock turbo with no bov, EXPECT the kent to blow a blade sooner or later!

i for one, ran 14 psi, on my hi flow vg30 for yonks, not a prob.

there are plenty of others out there who have the some opinion, joel for one.

f**k me.

well said craig

[steveP]

Flutter from blocked BOV = compresser wheel in the turbo suddenly spinning backwards and the sound comes through the pod filter.

turbos NEVER spin backwards! like said before, they can spin upwards to 150,000 rpm. they simple slow down and speed up depending on the boost.

correct Stevie, the air returning back through and slowing down the compressor and "chopping" the ait is what makes the vutututututu sound. Depending on pod filter design, it will be quiet or loud.

FAIL!

like said above, turbos spin at very high rpm. they dont 'chop' the air. the compressed air sits in the cooler/pipes, and as the blades slow enough, the boost pressure will drop to that rpm of the turbo. this happens graduarly as the turbo blades slow, which is why u get the tu tu noise.

and people f**king their engines/turbos with no bov. its not the lack of bov.. how stupid can u be.

[CRoNic...]

This goes nicely with this failure:

http://au.answers.yahoo.com/question/index...11175919AAUEDoF

[craig R33]

bahaha what a wanker

[CRoNic...]

Long explanation:

http://www.nissansilvia.com/forums/index.php?showtopic=28060

No bullshit in that single-post thread, either (even though it's ns.com)

/closethread

[Ryanrb25]

I've ran mine since I can remember with a blocked off BOV.

With the ceramic turbo running 1bar I covered around 100,000km's on the rb20det, then pulled it out for the rb30det. Still in good nick. I went a VG30 which was good for another 50,000km's and was still fine when I pulled that off, the Garrett gt30 I now run still doesn't use a BOV.

The GT30r has covered around 40,000km's now. Damn time flies. :S

The bov is there for emission reasons. Without a bov look what it does to your afr's on and afm voltage as you come off the throttle which causes stalling, back fires and some times flamage. Another issues is the strain it puts on your joiners/clamps. I had to replace some with t-bolts.

The reason I went no bov is the stocker was for the part throttle drivability. No bov you grab the next gear and boost is just there. Without a bov it felt laggier on gear changes as I presume it takes longer to fill the FMIC and piping than it does to regain the 'slight' speed the compressor may loose due to pushing against a pressure source.

Shaun/Boostworx runs track cars with no bov, no issues related to no bov. I know of multiple high powered RB30et's without issues running no bov.

+1 covered around 40-50,000km with my 31 with no bov and no issues.

listen to all the people that have actually done it, rather than those who think they know everything.

f**k me.

+1

too much of this these days,

[typevu]

sututtutuutuuu

[KISIN]

also have a look at some youtube vidoes of japs racing...most i have seen have flutter...you ever wonder why ?

Edited October 21, 2008 by KISIN

[Cubes]

Cronic...

lol @ the ns.com thread op. His forum name suits him well. A dumhead he is.

Again. Its primarily there for emissions and driveability. Not for performance which is exactly what I have found in my own fiddlings.

As for some one reputable that has a shit load of experience... Simon from Nizpro explains the BOV's use. http://www.nizpro.com.au/about.html

http://autospeed.com/cms/A_1457/article.html

"The blow-off valve is designed as an emissions control device for OE manufacturers.

"The airflow meter is not all that smart and does not realise the air is going in the wrong direction; it therefore measures the air twice (once going into the engine and again going out in the wrong direction). The computer now tips in twice as much fuel as what's required, making it run rich - making it not pass emissions.

"Therefore, manufacturers fit a blow-off valve - or a recirculation valve as they are actually called. A recirculation valve opens when it senses manifold vacuum, returning the air trapped at the throttle body to between the airflow meter and the turbocharger. As such, the airflow meter does not take a double reading - the car now passes emissions.

There's a market out there for replacement 'high performance' bov's as people believe it 'stalls and breaks' the turbo. Don't believe those that sell and market BOV's.

[mrgtt]

what ever happend to that gtr wanted to sound like an sr flutter thread?

[Cubes]

Maybe its here? -

lol

[TS-R34]

what ever happend to that gtr wanted to sound like an sr flutter thread?

LAWL

[mrgtt]

Maybe its here? -

lol

wow sounds nice i have the t88-34D not sure if it will go on my gtt though

[Import S13]

i ran no bov on 240rwkw s13 on the track cause when i compared running a atmo one vs none at all i found i had less lag through gears under hard boost which was awsome for turn 1

i was told not to run no bov running that much boost but did it anyway and the turbo out lasted the motor but thats an sr for you!

on my 32, im running no bov again and its still going fine. also going through heaps of crapy boring tests with the sil i found running a atmo bov the car was stauling more but im guessing the spring rate or something had something to do with that but never bothered to fix it as i like no bov at all!

also have to remember some turbo cars come out facotry without a bov like the ca18det's and i see them out lasting sr's everyday!