Ive just replaced my DV30 Recirc with a DV26 from Jap.

Now when I lift off i get a strange noise I can best describe as link an echo sounder from a submarine film followed by the dump valve release. Whats the noise and what have I done wrong?

Does it sound like a churp noise ?

Um sorta...

Its not the actual dump valve "hiss" but before that I'm getting a kind of "Boc" noise

just to add i have a Apexi Filter, SIP, GT28R and FMIC if that makes any difference

I have a DV26 and along with the dump noise i get a churping noise which i think is the air going back through the blades on the turbo and its a very common noise, someone will correct me if im wrong

is it a dv26d or a dv26 as the dv26d comes with a harder spring so the coupe might not be able to move the piston

It will be the sip hyperlink, it sounds abit like a pigeon getting randy I noticed mine after i fitted the sip, does it more on low revs and low boost. Its a normal noise you get from the sip, it got me abit worried when i first fitted it all.

Ash

This is what I guessed it might be - is this whats called flutter? Sorry if I'm being dumb but I never used to hear anything like this with the recirc as i just got the air dumping through the filter instead.

Randy Pidgeon - I like it describes it pretty well. Ive not had a chance to test it fully as my AFM is FUBAR so I'm taking it steady until its fixed.

It's because the spring is too strong and not opening at low boost, thus, the air goes back over the compressor blades and gives you the "randy pidgeon" noise

So this is not a problem then?

My DV26 does the exact same. It needs serviced/lubed every week but I think this *may* be down to Methanol killing it.

use mobile one grease/oil

I just fitted my randy pigeon/DV26, and am getting a similar effect. For some reason I really cant hear the thing when lifting off, just in 1st and 2nd change. Will the spring 'loosen up' a bit? (BTW I double checked I ordered just the DV26 not the DV26d)

Also can we summarise it's nothing to worry about?

Barks

i have this too i must admit it gets annoying... i have some more springs, would a less stiff one cure it?

If the spring is too soft it will leak boost, too hard and it will take more pressure to open than it takes to force the air back through the turbo instead, which is what gives a wohwohhw kind of sound

have you put the d/v on correctly

I have a new Bailey DV30 and I get the same flutter, wondering what to do about it...

if the d/v is mounted in correctly it will flutter and the recirc do tend to make a flutter noise as its putting the boost presure back in the system cause the air to flow back through the turbo cause turbo stall thats the noise you hear