BOV Blocking ..

[mindflux]

Hey i have taken my BOV off my car, and i was wondering what methods people use after they have done this.

I simply got a plate made up that screws over the outlet on the engine.

I know you can place the stock BOV back on, but i choose not to do this.

just wondering how everyone else did theres, just so i know if there is a different way then what i did.

[Col-GTSX]

Mate... I had no blow off valve at all. But i makes a funny noise of chopping air as the compressed air passes back over the impella. This not only puts pressure on the impeller but it makes the noise of a blow off valve anyways. The police were gonna write me a ticket for having a loud blow off valve and when i popped the bonnet and show them there was none. They told me to put a standard one on because they make very little noise. If i didnt then next time they will fine me....

[robbo31]

gday guys, just if you're wondering, some very interesting reading along the lines of BOV's , having 1 or not, and its affects on the turbine and associated systems

http://ausrotary.dntinternet.com/forums/vi...c&highlight=bov

[mic_sky]

I know you asking in regards to the intake pipe.

but i also want to know what people use to block up the unused hoses.

[mindflux]

I took my BOV due to my readings about them. and my personal beliefs about them.

when running no BOV (not even a tock) .. you do get the flutter of the waste gate, this is why nissan placed a stock BOV on there cars to get rid of the sound.

the logic behind this is ...

the older people want a family car that doesnt drive around making pigion noises.

if any of that makes sense?

[mindflux]

Mic Sky - Well one of the houses (the fatter one) has a cap on the end

and the thinner one is currently cut right back with a bolt in the end of it.

I am going down to a few shops tomorrow and seeing if i can get a cap for the thinner hose.

if not im goilg to weld a little nipple/knob on to the flat custom cover so it just stays blocked and plugs in there .. just so it looks neater.

I will take a photo to explain what i mean when i get it done

heh .. sorry

[Dynamix]

I was under the Impression that a bov was fitted to give the turbo longlivity, to reduce the back pressure over the impella which puts stress on the turbo, not so some old fart could drive in peace, if you where running the stock intake box then you wouldn't hear much sound with or without the stock bov....

[mindflux]

Good point...

However im unsure how much longlivity it would give wiht or with out a bov.

Not to sure how a plum back bov works, im a bit rusty on that knowledge ..

but wouldnt that be doing the same thing as runnign with no bov?

eg: putting the pressure/air back through the turbo?

i think i might go do some reading on this so ..

[Dynamix]

Plumback = venting excess boosted air through the bov back into the turbo inlet pipe, a stock setup and a ' legal ' setup is plumback.

When you are running no bov you get chopping of the compressed air going back over the impella, think of it like this, if you run no bov exhaust gas is trying to push the turbine blade one dirrection, and the boosted air has nowhere to escape but back through the impella pushing its way back through it going the exact opposite direction as the air is supposed to be travelling thus putting stress in the turbo, exhaust gas pushing one way, excess boost pushing the other way, something has to fail unless the access air has somewhere to go when the throttle is closed.

[R33vit]

Good point...

However im unsure how much longlivity it would give wiht or with out a bov.

Not to sure how a plum back bov works, im a bit rusty on that knowledge ..

but wouldnt that be doing the same thing as runnign with no bov?

eg: putting the pressure/air back through the turbo?

i think i might go do some reading on this so ..

not using a BOV will not only shorten the life of your Turbo but will also cause the turbo to slow down between throttle off's, hence making it feel laggy as the wheel needs to pick up speed again when you get back on to the loud peddle..

[NewKleer]

lets see if i have this right, (sound/wankfactor aside)...anything ive missed?

Atmos BOV:

For:

1) keeps turbo happy

2) less gear change lag than all (with a/m computer)

3) doesnt insert hot (from compression) air back into intake

Against:

1) afm counts more air then really there - need aftermarket computer to stop rich gear changes

2) illegal (due to emissions, ie running rich on gear changes?, and/or noise pollution?)

Plumback BOV:

For:

1) keeps turbo happy

2) less gear change lag than no bov?

3) doesnt mess up afm readings, wont make run any richer on gear changes

4) legal

Against:

1) inserts hot air into intake, (= slightly less power due to less air density)

No BOV

For:

1) more legal than atmos (may be illegal due to emissions on gear change?)

Either way:

1) mildly heats air into intake, not as much as plumback (from chopping + recompression of air that went back thru turbo)

Against:

1) turbo wont be happy due to chopping

2) gear change lag

3) counts air twice on gear change (= runs rich unless a/m computer?)

[Tosh]

sorry to go OT but...

:) @ NewKleer's Avatar!

[mindflux]

Lol ill back up that avatar too

Ive found running now BOV has stopped my car from runnign rich.

im still investigating the pros and cons.

Every Bov leaks... find me one that 100% has no leaking ever and you can be my australian idol

so you loose power there.

In short the only happy solution its seems is to run a plumb back blow off valve.

any even if it put hot air though your turbo, unless you doing some serious racing, i feel this is really irrelevant.

I feel in the long run. if your running a stock turbo at stock boost any of these peoblems listed above are much of a nothing.

but thanks for the info guys. keeping me educated

[Trust33]

Hi when you have got two blow off valves like i have (R33GTS-T) a stock one and an aftermarket one is it at all posible to remove the stock bov,cover it over accordingly,plug up the recirculation holes in the intake pipe and have no problems with the cars performance whatsoever?or would it be better to just replace the pipe going over the motor all together???...........It is also my knowledge that if the bov doesnt retain the recirculation that it is fineable by the epa and the police all because of the oil mist that runs through the intake pipes being thrown out into the atmosphere with an externally venting bov.Much like the oil catch can enclosed (ok) externally vented (not ok)