BOV sound

[trbo32]

Hey guys does anybody know how to get that stuttering sound when ever you let go of the accelerator. I hear a lot of VL turbos’ that make a descending stuttering sound as apposed to the single whoosh (something like that ) mine makes whenever I let go of the accelerator.

I heard that if you block or remove the BOV then it will make that sound. But doesn't removing the BOV cause damage to the turbo?

If anyone has seen the Drift Bible, the guy's S14 makes the sound I’m talking about.

[BIGBLOCKR31COUPE]

That sound is air bashing the sh1t out of your turbo. That is the reason cars have blow off valves. Some people like the flutter sound but if you are intending to extract any power from your car and you want the bearing in your turbo to last a while.....no good. Every time I hear that sound I cringe. Blow off valves are not there for noise, they were designed to prolong the life of the turbo.

[MJ]

Yeah man dont do it the sound is from the air going back through the turbo chopping the air, not exactly good for it and can shorten the life of the turbo

[QuickR33Melb]

I have a turbo HKS BOV fitted that makes a nice sound.

For those that say the power drops I didn't notice any change once I installed it other than everybody on the street snapping their necks to see my car rolling past. lol.

If you want a nice sound buy an adjustable aftermarket BOV and play around with it until you have the desired sound

[red17]

Most BOV's will flutter at low RPM gear changes, usually when the turbo isnt moving at a high rpm so damage is pretty minimal. Even my standard bov used to make the flutter sound so it cant be doing damage from the factory.

As long as once the car builds boost you arent hearing the flutter and instead have a nice solid psssscchhttt sound then you should be right

Red17

[DJ984]

i've got a GFB hybrid BOV set to 'flutter' under about 3000RPM... the guy at GFB explained that if you keep the flutter down low the damage is so minimal you won't notice it....

[Guest RedLineGTR]

i've got the same u can adjust it abit more but a get flutter untill 2800rpms-3000rpms unless i';m actually got down then it dosent flutter much at all. It should be fine.

[Cool Hand Luke]

I'd like to see how much damage it does, my 180 when i bought it had a blocked BOV and wasnt working since new... actually it was incorrectly plumbed. It was running 27psi and 4ich pipe from the intercooler so there was alot of air, and had driven 20,000 hard kms like that and is still going fine. It sounds unreal, it was that loud it used to echo off buildings in cities, but i got it fixed after a few weeks of owning it.

[BIGBLOCKR31COUPE]

The gibson motorsport R31s didn't use a blow off valve but that was in the 80s.

[whistla]

I ran no bov with my old stock turbo for a year and clocked close to 50,000km in that time.

When I upgraded my turbo, I had my old one checked out, it was in perfect health (running 14psi)

Just bare in mind, "mums and dads" that buy a turbo car dont like noises emitting from their cars everytime they change gears.

To some; noise = somethings wrong, so the last thing most want is a muffled fluttering noise.

Plus, together with a factory AFM and tight emission regulations there is a need for the plumb back return pipe.

But you make the judgment, so far in my life i havent heard anyone prove to me there is inevitable failure by running no bov.

[DJ984]

If you don't run a BOV at all (on a R32 GTS-t for example)... will that cause all the backfiring and stalling that a straight to atmo one would???

[DJ984]

so far in my life i havent heard anyone prove to me there is inevitable failure by running no bov.

as the guy from GFB told me, they used to build turbo cars without BOV's anyway so it can't be that bad....

[trbo32]

I have heard a lot of high performace cars running with the flutter sound. WRX's come out of the factory with no BOV.

I guess it comes down to how you want to treat your turbo. I have heard of cases were turbos were running high boost and the driver let of the accelrator and the intake of the air bent the impeller blades back, stuffed the turbo. But these are in extreme cases.

Not sure what i'm going to do.

Does anyone know how to block the stock BOV on a R32 GTS-t?

Also, are you able to make the stock BOV dump to atmosphere?

[pinoi_boi_r33]

dude, y don't u try some aftermarket sequential blow off valves? Seqential meaning venting the pressure internally and also venting into the atmosphere. A lot of these BOV's make the fluttering sound you desire. Since you are in Melbourne AVO in Cheltenham make their own and also the HKS super sequential Blow off valve is a good choice. There are many others out there but those are just some examples. But remember that any BOV that vents to the atmosphere does not pass emissions and if u go around parading yourself you'll get defected. Doesn't really matter tho if it ever does happen its just one pipe and u replace it with the stocky intercooler piping.

hope i've helped a bit.

[DJ984]

WRX's come out of the factory with no BOV.  

Also, are you able to make the stock BOV dump to atmosphere?

Are you sure? i thought rexies had an internal one of some sort?...

should be able to make the stock go to atmo... just remove the rubber tube that goes from the bov to the turbo (the big one)... that should do the trick...(dunno honestly but that's what i'd try)...

Also, to block it off, take it out and cover the whole with a flat metal plate...

the two above raise the issue that i asked in my previous post... Will no BOV cause stalling and backfire????

[R31Nismoid]

I have heard a lot of high performace cars running with the flutter sound. WRX's come out of the factory with no BOV.  

I guess it comes down to how you want to treat your turbo. I have heard of cases were turbos were running high boost and the driver let of the accelrator and the intake of the air bent the impeller blades back, stuffed the turbo. But these are in extreme cases.

get your facts straight first.

how well you treat your turbo?

so what, your never going to make boost with it so it's stays like brand new???

ALL turbo car's in the 90's come out with a BOV. INCLUDING WRX's.

just because you cant hear the big PSSHT... of the aftermarket BOV as it's a plumb back (as all factory BOV's are), shows you obviously dont know what your listening for.

the two above raise the issue that i asked in my previous post... Will no BOV cause stalling and backfire????

YES. amongst other issues, bad economy etc.

BIGBLOCK...

The Gibson car's didnt run a BOV, yeah, but did you know they rebuilt the turbo's after each meet???

So there is no need then is there is your always rebuilding them anyway.

Also the were using Bush Bearing Turbo's... not more costly Ball/Roller bearing ones.

The cars/drivers could shift a bit faster too so there was less pressure going back onto the turbo etc.

And lastly, the R31 GTS-R's i dont think came with a BOV factory.

Im not quite sure how that would fit into the Group A racing rules...

that's one thing i'm yet to know about my GTS-R yet (bov or not).

But i be will finding out about it soon as a see other examples here in Vic.

so far in my life i havent heard anyone prove to me there is inevitable failure by running no bov.

A turbo will inevitably die anyhow. BOV or no BOV. How long this is... well that could be debated for ever.

It's like how long is a piece of string.

With no BOV it'll just bring it on a little sooner.

How much sooner is so variable and debatable im not going to go into it as it'll always be one side vs another.

Look at my car's turbo... it's ROOTED, it's been running no BOV and it's totally buggered.

I'm 99% certain that when i get my new turbo, run a bov, that it will be far more beneficial for the car and turbo.

[R31Nismoid]

apart from the above..

use the search button

try a keyword of flutter.

this has been and gone in discussion about a MILLION times

[LowRollaBoy]

Yes it will cause backfires runngin Bovless (afm/maf takes double reading) no it wont stall the car.

[R31Nismoid]

Yes it will cause backfires runngin Bovless (afm/maf takes double reading) no it wont stall the car.

It CAN cause your car to stall.

My car is living proof of it on an RB25 with stock ECU running no BOV.

maybe mine is more pronounced as it has a bigger turbo... ie, more air flow ?

[BIGBLOCKR31COUPE]

R31Nismoid- The R31 GTS-Rs did not come from the factory with a blow-off valve. Very few cars at the time did. You are 100% right about the turbos being rebuilt all the time. I am a firm believer in the blow-off valve for prolonging turbo life but just thought that I would mention the old Gibson R31s. The example that was in zoom magazine last year had been fitted with one at a later date. You are right that WRXs do come standard with one (I sold them in the late 90s).

trbo32- you should be sure of things before you state them as facts.

my 2c

Geoff.