Dump Valve or not?

[Bison]

I had a dump valve on my last T5, and as much as it sounded lush, I swear it made it a little slower, I had to blank of the re-circulating Valve as well. Now the sound I want is really the wastegate chatter, in order to get this i will need a cone filter and to blank of the re-circulating valve, are there any dangers in removing the re-circulating valve and not adding a dump valve?

Bison

[Bracer]

Simply the flutter you hear on an internal W/G turbo is not W/G chatter its the compressed air rushing back to the turbo when the throttle plate is closed and the compressor blades chopping into the air which is a BAD thing

Either leave the CBV in place and try and make that more audible or sack it off and fit a BOV

Steve

[Wobbly Dave]

Wise words indeed. I think it is unwise to fit stuff like this if all you are after is the noise.

[Bison]

Simply the flutter you hear on an internal W/G turbo is not W/G chatter its the compressed air rushing back to the turbo when the throttle plate is closed and the compressor blades chopping into the air which is a BAD thing

You get that chatter noise as soon as you fit a cone filter/induction kit don't you?? I've had that on my Cossie & my 200sx. I didn't realise it was bad for the car, why is that?
Bison

[Bracer]

You get that chatter noise as soon as you fit a cone filter/induction kit don't you?? I've had that on my Cossie & my 200sx. I didn't realise it was bad for the car, why is that?
Bison

True W/G chatter is only made by external W/G's. The noise you hear on a internal W/G turbo which is similar to the chatter, is as explained and is very destructive to the turbo, which usually results in the bearing being knocked out and the compressor blade hitting the turbo housing thus exploding the wheel and sending thousands of pieces of metal into the engine destroying that too.

I found that once I went over 18 Psi the stock CBV couldn't relieve the system of the built up pressure quick enough giving me the chatter noise and compressor stall creating more lag when I got back on the gas, thus the need for me to go over to a BOV capable of flowing over 25 Psi.

Steve

[Bison]

So how can I get that noise without blowing my car up? Or shall I leave that and take the safer option of a dump valve? I want a noise!!!

Bison

[Bracer]

So how can I get that noise without blowing my car up? Or shall I leave that and take the safer option of a dump valve? I want a noise!!!

Bison

Simple Get a BOV and blank off the CBV

Do a search for BOV as its been discussed quite a few time, and then if there is anything your still not sure of give me a shout

Steve

[Ross9]

You will get a chatter just by using a cone filter and aftermarker BOV, you may even get it with just a cone filter and the standard recirculating DV, ont sure about Volvos but the Rovers chatter just with a cone on.

Bracer is correct in saying that the noise is due to backflowing pressure, it is undesirable, but unless your running major boost it wont cause the turbo to explode spectacularly.

jacqs T4 has been running a Forge BOV and cone filter for ages now, and it still chatters on part throttle change ups, ie lifting half off in gear, so not totally releaving the pressure on the DV in order to get it to fully open. Turbo still works fine and holds its higher than standard boost levels, no smoking.

Ross