R56 Blow Off Valves - Opinions?

[R99]

Hi guys,

With no one in the UK seeming to be interested in doing anything with the R56 (even though its been out since 2007!!!) I am just wondering what people think about upgrading the BOV?

It seems quite a popular option in the US.

The Forge one is not really a proper solution, its more like a spacer on the stock factory diverter valve, and has been known to cause CEL's.

Now comes the interesting bit. The R56 is fitted with a "noisemaker" in the 'cold side' boost tubing. Part number 13 in the below diagram.



The function of this part is to vent noise towards the cabin (behind the firewall) nothing more. At the end of the tubing, is the 'noisemaker' itself. It does not vent any air out, it simply vibrates a diaphragm in order to provide a sportier sound to the driver.

US vendors offer a delete option to this, and claim ~2-3 bhp by doing so as it supposedly robs approx 0.2 - 0.5 bar of boost.

This is also the place where most proper after market BOV's are installed. Here are some sound clips of the options:

Helix 13:



Riss Racing:



HKS:




What do people think?

[Jamesf]

were having a prototype made atm

[neilobe]

I had the Forge BOV on my old S, didnt produce any problems or cels, but the noise of it drove me mad after about 2 months so took it off.

If your using the car everyday would you really want one of these hissing away evertime u touch the gas pedal..

[R99]

The Forge one is awful, it sounds like Darth Vader's helmet, but these more expensive systems seem to have more of a 'chirp' to them.

I guess I'd have to hear one for myself to make my mind up, but I've heard several Forge ones, and they all sounded bad

[neilobe]

Indeed they do sound bad the forge one, in fact on the chav side...

The HKS one is £500 isnt it? Not much performance gains for the outlay surley..
Id prefer to have more exhaust sound than one of these, but the correct exhaust sound, was follwoing a Evo the other day with popped and banged, thats what id be looking for from mine

[Coopman7]

The forge one i found was great fun. But only sounded good with an open filter - it makes a very different noise this way but as R99 said it does cause (ocasssionally) a CEL which does reduce power unless you turn off/on the engine OR use a code reader to reset. The CEL only happens on tuned cars running more than stock boost and occurs every so often when you put your foot down (building up boost quickly) and then lifting off right away.

I love the hks ssqv on mine but i dont have the recirc valve anymore but ive heard a few on youtube and they seem to sound good and no complaints about lag etc

Originally Posted by neilobe

Indeed they do sound bad the forge one, in fact on the chav side...

The HKS one is £500 isnt it? Not much performance gains for the outlay surley..
Id prefer to have more exhaust sound than one of these, but the correct exhaust sound, was follwoing a Evo the other day with popped and banged, thats what id be looking for from mine

The best one i have seen for the R56 is the exhaust depot one and im sure you can get the induction pipe/bov kit for alot less than £500.

If you want pops and bangs (assuming your tuned ?) then remove your resonator from the exhaust - it wont sound this good but it will pop and bang more

[R99]

Originally Posted by neilobe

Indeed they do sound bad the forge one, in fact on the chav side...

The HKS one is £500 isnt it? Not much performance gains for the outlay surley..
Id prefer to have more exhaust sound than one of these, but the correct exhaust sound, was follwoing a Evo the other day with popped and banged, thats what id be looking for from mine

The HKS is £300 from Lohen, but even still its a lot of money!

I've got my exhaust sounding pretty much perfect now. It pops and bangs really nicely.

Originally Posted by Coopman7

The forge one i found was great fun. But only sounded good with an open filter - it makes a very different noise this way but as R99 said it does cause (ocasssionally) a CEL which does reduce power unless you turn off/on the engine OR use a code reader to reset. The CEL only happens on tuned cars running more than stock boost and occurs every so often when you put your foot down (building up boost quickly) and then lifting off right away.

I love the hks ssqv on mine but i dont have the recirc valve anymore but ive heard a few on youtube and they seem to sound good and no complaints about lag etc

Have you had the Factory recirc / diverter valve blanked off then? Or do you mean you have had the HKS one modified?

[Coopman7]

When i fitted the new turbo kit i had done a deal with a guy on NAM i swapped my Ragazzon decat for his exhaust depot hardpipe/bov kit. And the new turbo doesnt require the electronic valve so its removed from my car.
The pipe fits just after the tmap sensor (to left of engine) and fits perfectly onto the intake/throttle and doesnt have a hole or connection for the sound maker as this is not needed for any purpose (unless you wanted to keep the car totally stock).

If i had got a proper bov when i had my tuned k03 turbo i would prob have got the hks still but would have considered getting the alta block off plate for the recirc valve but i dont know if the ecu would need tuned for this.

[R99]

My level knowledge has ran out. I dont really understand the above.

I think this the exhaust depot hardpipe kit you are referring to?



I'm guessing one is the intercooler outlet pipe (part number 8 on the Real OEM diagram)

The other hardpipe must be a replacement for part number 8 on the real OEM diagram?

There website offers it with or without a BOV, so I'm guessing if you choose without, then you just have a noise-maker delete 'bung' welded to the pipe instead of the the opening for the BOV?

[Coopman7]

Originally Posted by R99

My level knowledge has ran out. I dont really understand the above.

I think this the exhaust depot hardpipe kit you are referring to?



I'm guessing one is the intercooler outlet pipe (part number 8 on the Real OEM diagram)

The other hardpipe must be a replacement for part number 8 on the real OEM diagram?

There website offers it with or without a BOV, so I'm guessing if you choose without, then you just have a noise-maker delete 'bung' welded to the pipe instead of the the opening for the BOV?

The top pipe in the picture is a replacement for the turbo to intercooler standard pipe which has the muffler (number 9 on realoem diagram) and the lower pipe is the one i have (this fits where number 7 and 8 are on the realoem diagram).

You can have the one i have without the bov and so it would be a noise maker delete (im not sure they do a bung for the noise maker to fit onto).

As for my previous post i was just saying i dont have an electronic valve anymore because im using a different turbo and so your best to ask around for those who are running a mechanical bov with the standard electronic valve... Ideally you would want to hear from someone who has fitted a mbov and blanked off the electronic one with the alta block off plate.