Stock dump valve

Hi everyone, is there a way to test the recirculating valve on our cars? I get a strange noise at about 2.5 to 3k revs then the noise stops, only lasts for a couple of seconds.

I’ve not heard of one. Other than swapping it out for one from someone else to see if the noise persists. :thinking:

Dont know whether to go atmospheric or a decent recirculating. Some say atmospheric ones make these cars run rich, someone with more experience than me may be able to advise.

The problem with going atmospheric, is that your losing air, that’s already been ‘measured’ by the ECU, which causes the rich condition. Technically, that blow off air, also helps keep the turbos spinning.
My opinion is there’s no benefit for going open air, other than noise.

I’ve just read that the sort of honking noise I hear at mid boost is probably coming from my twin mushroom air intake.

The honking is from the stock bov, usually starts when you add an intake to a stock system.
A nice cheap option, is find a used DSM bov… It’s a bolt on for us, same look and shape, but it’s built better - no honking.

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You can change “probably” to “is”. It’s well known that a less restrictive intake does this. It could be the stock air box made it impossible to hear it before.

Yes I think so but twin mushroom was on car when I purchased it so I cant say for sure.

I had the experience of before and after with a stock air box, and a K&N FIPK, and it freaked me out when I heard the honking goose noise.

How did you solve this?

I replaced the stock BOV with a Greddy Type-S with recirculating adapter. I did buy a more expensive HKS unit, but had problems with it. The Greddy Type-S worked great on my friends car, so I bought the same type and had good results. A few years later, ebay started selling knock off version of the Greddy Type-S at one quarter of the original price, but I don’t know if they exist anymore, as Greddy discontinued it.

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