'forge' style dump valve

Is this cheap option any good?

http://www.ebay.co.uk/itm/FORGE-BAILEYS-...12#ht_500wt_922

No experience with it but personally, I would steer away. You can get second hand Bailey or Forge for the same money. I had both in my VT's and they never failed.

It should be ok. Put it this way, there is no chance of it splitting like the standard Bosch one so therefore must be better!

I'd be looking at buying a second hand Forge, no way of telling the quality of that one.

Thanks guys. About two minutes ago I bid on one as it was auctioning for 10 quid and won it! Only a tenner so went for it. I'm ideally after a forge dv006 but half tempted to give this ago in the mean time. Need it to be a stronger than standard dv as putting my gtec1 chip in this weekend.

I bought one of those for my Leon Cupra R, It was fitted with too stiffer spring, I tested the car and had turbo surge from it not functioning freely enough and bent my turbo blades intake side, Cost me £500 in total!

Buy Forge / Bailey etc.

Or be sorry.

DVs on a Coupe don't need to be strong, as the pressure should be on the side of the piston, not the end

Most people with a Forge run the weakest spring, regardless of the state of tune - I have done for years

I was under the impression that if I'm running a constant 1.2 bar then the standard dv will eventually leak so that why i need to upgrade?

Yes, the standard DV isn't really up to holding increased boost, but it is the DV design, rather than the strength of the spring that is poor.

When correctly oriented, the pressure (ie the hose from the solid plastic pipe by the side of the camcover) should enter the side of the DV - that way ANY amount of pressure won't open the DV

The DV is operated by vacuum in the small-bore pipe - this lifts the piston in the DV and allows pressure to vent through it to the inlet ahead of the turbo

Because of this orientation, the DV spring only hs to be able to keep the piston seated - it doesn't have to "fight" the boost pressure - because of this, the DV spring can be really light.

If you fit a heavier spring, there will be times when the DV doesn't operate after you lift off the throttle, which could cause mild compressor stall

I fitted one of these to a Coupe about 5 years ago, it's fine and hasn't had any problems.

good stuff and thanks for the info nigel. assume using the harder springs on a forge and causing compressor stall would account for the pigion sound. when i do finally get a forge i will make sure i get the green spring. but for now im glad this option is ok to use on my car

missed chrissy's post. have just contacted the seller to ask about spring strengths. hoping this would be similar to a forge dv006 green spring, however I dont think he will know.

If I do hear compressor stall, then I will remove and get forge/baileys immediately.

thanks all.

--update -->

ebay seller confirms you can change the spring on this valve (buy from forge) and it currently has a spring suitable for 'standard to slightly higher boost'. so whether that would mean 1.2 bar i dont know

I have one of these fitted and is soooooo much better than the original bosch, holds boost (unlike the standard).

Wow. Really?? What convinced you that it was running with a non-opening DV that caused the failure and not, for example, worn bearings, or foreign object ingestion (eg, grit)?

Not that I don't believe you, I'm just very interested to find out as more about the circumstances. I've been searching for proof of the woes of running without a DV for ages and you're literally the first in all my knowledge and seemingly the whole of the internet who's actually attributed a turbo failure to a non-functioning DV. I even contacted Owen Developments recently and they couldn't give me any examples of turbo failures due to not running a DV - in fact they said they run their own race cars without!

Can you remember more details about the turbo; age, boost? Do you have any pics? You can PM me if it's going to throw this thread off-topic.