I fitted my forge dv004.
I seem to of started getting a chattering noise when i lift off, just like the first group A sierra cosworth rally cars, which i gather is the wastegate.
Does anyone know what it is exactly causing the noise, and also if this is a bad thing or not, i seem to remember reading in the old forum it was!

Cheers
Phil

If it is wastegate chatter, which it sounds like it is, then just enjoy it cos it's a cool thing, it does it every time you lift off, as far as i know there is no harm in it.

Ive done a bit or reading and it looks like its the turbo stalling! which is surely the opposite of what a new dump valve is meant to do.
I think its also called compressor surge.
I love the sound, but just hoping its not doing any damage!

your right, its the air that hasnt been dumped out going back across the compressor blades, which in turns stall's it, thus making the noise. If your getting it, its possible that the spring in your dv maybe too strong and not letting all the air out

I got this noise when my old DV was dead.

so what does wastegate chatter sound like? an dwhen should it happen?

There isnt such a thing as wastegate chatter, the stalling is what people refer to as wastegate chatter

You know the funny whooping noise Dr Zoidberg, the lobster, makes in Futurama? Well it's a bit like that.

oh ok, So my next one then, is it a bad thing, can you do anything about it?

Thats still the stalling, the higher the boost being pushed / dumped, the noiser it gets. say you backed off at .2bar you would get a ffffpptt fppptt fppptt at higher boost you get the louder "Dr Zoidberg" noise <img src="/forum/images/graemlins/laugh.gif" alt="" /> Easy eay to test is to block your vacuum feed to the DV then see what noises it makes

will it bust anything beggars?

No, although people say it will kill your turbo, but i havent heard of anyone in doing so. Some of cosworth lot will run 2bar and not use a DV!

Cheers Begbie

Cant wait to go out again to here that chatter!
Once the novelty has worn off think i might go back to a recurc valve.

Cheers everyone
Phil

I drove a Turbocharged Focus built by GSE over to Ireland which made a lovely wastegate chatter.

I'm very jealous Phil. <img src="/forum/images/graemlins/smile.gif" alt="" />

i thought it was ment to make that noise lol, mines been doing it for ever!!

You often find that it will do it when you have a high-boost but relatively low engine revs so there isn't enough vacuum to open the valve. I can make mine do it by accelerating hard in 2nd from low speed and then lifting off when it gets to about 2500rpm but it's not something that should happen during normal driving.

That's exactly the conditions mine does it and that all makes sense to me now scooby, nice one

hmmm my car makes this noise too, whenever u change gear after high boost.

My mate who i bought the car off said it was "the cool noise that the standard recirc valve makes" so i just assumed it was basically the equivilent noise to a Dump valve's 'Phsssh'.