Recirculating BOV do i really need to replace?

[Luke]

Agreed, A new BOV will do Sweet FA. It's the noise that makes people think it's actually doing something, save your money.

[Ranton]

ill pull mine off tomorrow see if i can pressurise it and see what happens..

if faulty me thinky a new blacko plastic one will do me fine...

[Ranton]

I bought the forge BPV in the first picture.

The difference is not staggering, but there is one.

You will find lag when changing gears is a little less, and that the engine seems to pull harder further into the rev range than the standard plastic fantastic BPV does.

The side mounted Forge BPV also makes no real noise at all. I was told to expect a cash register sound, but nup, nothing.

Personally I recommend it.

So What springs were you guys using in your valves..

I recieved mine today

and it came with the Yellow Pre installed and the Red and Blue one in the box?

[DISIMS3]

Most people who reviewed the valve in the US say the blue spring works best with our cars.

[Ranton]

Hmmm.. Im running with the Yellow So far under fullish boost there is a slight flutter..

Will chuck the bluey in later on.

Take for a Drive..

[Doug_MPS6]

Ranton, Hi, if you were really "giving it stick" in 6th at only 3000 rpm, and I'm assuming by that you mean that you were flat to the floor, it's highly likely that it was not your BOV fluttering and leaking but your wastegate dumping off excess boost, as you had a high load at relatively low rpm.

There are distinct differences in the sounds made by each, and if you were on throttle, the BOV should not have activated anyway, for the reasons I defined before, as its piston is under neutral pressure.

6th is a very tall gear with a big step up from 5th and is best treated as a cruise gear, with serious pull needs best being left to 5th.

Any issues I have with boost relief or slowness of the BOV to dump all that FMIC (and related plumbing)-contained boosted air as fast as I would like on throttle lift-off come in 6th at relatively low turbine spindle speeds.

I can't recall when I floored it in 6th, if ever, but even at ~30-50% throttle opening and ~3,000-4,000rpm, the amount of air dumped on sudden and total throttle closure easily exceeds that handled by bypass and vents huge amounts immediately and noisily to atmosphere, almost enough to sweep the streets clear of leaves!.

(We read here a while back of some member wondering why his engine would rattle badly and blow smoke when flat to the floor in 6th at 1500-2000rpm!! That was his poor engine about to have conniptions due to relatively high boost levels at high engine loads. We don't know what octane rating fuel was being used, though that appears to be academic at this combination of rpm and TPS).

Hope this helps. Cheers.

[Ranton]

Ranton, Hi, if you were really "giving it stick" in 6th at only 3000 rpm, and I'm assuming by that you mean that you were flat to the floor, it's highly likely that it was not your BOV fluttering and leaking but your wastegate dumping off excess boost, as you had a high load at relatively low rpm.

There are distinct differences in the sounds made by each, and if you were on throttle, the BOV should not have activated anyway, for the reasons I defined before, as its piston is under neutral pressure.

6th is a very tall gear with a big step up from 5th and is best treated as a cruise gear, with serious pull needs best being left to 5th.

Any issues I have with boost relief or slowness of the BOV to dump all that FMIC (and related plumbing)-contained boosted air as fast as I would like on throttle lift-off come in 6th at relatively low turbine spindle speeds.

I can't recall when I floored it in 6th, if ever, but even at ~30-50% throttle opening and ~3,000-4,000rpm, the amount of air dumped on sudden and total throttle closure easily exceeds that handled by bypass and vents huge amounts immediately and noisily to atmosphere, almost enough to sweep the streets clear of leaves!.

(We read here a while back of some member wondering why his engine would rattle badly and blow smoke when flat to the floor in 6th at 1500-2000rpm!! That was his poor engine about to have conniptions due to relatively high boost levels at high engine loads. We don't know what octane rating fuel was being used, though that appears to be academic at this combination of rpm and TPS).

Hope this helps. Cheers.

Lol

No im talking 3rd Fourth and high Rpm so no a excessive loading on a poor 6th gear at low rpm

the slight Flutter is heard in conjunction with the intake noise..

[KRNAGE]

dont use yellow unless v2 is a bit different, at least blue and then start to add shims - youll feel the difference. im about to go back to blue +2 shims to see how it goes (v1 here, with wutang swords )

[Hama3]

Ranton,

Where did you purchase the BPV? Was is Street Unit or RPM store?

[Doug_MPS6]

Hi Ranton, if you are sure you are throttle-on and you are hearing induction noise and a flutter then it means you are still generating boost and your flutter may be wastgate doing its job.

A BOV should only produce a noise when the throttle is closed. The wastegate bypass sounds more like an intermittent pssshht....pssshht....pssshht, accompanied by apparent loss of or reduction in boost.

A closed throttle activating the BOV to Bypass (whether setup to 50:50 or 100%) will sound more like a fast, progressively downtoned whoo-whoo-whoo. If you are set up to 50:50 Bypass/VTA and boost has been more aggressive, closing the throttle will activate the BOV to produce the initial whoo-whoo-whoo to Bypass but also the often heard loud pssssshhhhtt (beloved of tuners) as the excess is vented to atmosphere (VTA).

If you don't have a BOV opening due, say, to a malfunction, or perhaps one that is screwed down too tight, you will prevent it opening to Bypass or VTA, the result being that the boost pressure wave backs up against the turbo and stalls it, producing a fast downtoned whrrrr..whrrr as the turbo spools down rapidly. Preventing this is the sole purpose of the BOV.