[Tall-Paul]

As above....ive got nearly all the engine mods possible including a dreamscience cais but I dont get any turbo chatter when backing off the throttle. When I got my stratagem reflashed at dreamscience HQ jared took me out in his st which chattered whilst driving, it also chattered when revving the engine hard enough.

I was think there may be a problem with the dump valve or something being a bit to slack???? All help appreciated

Paul

 

[scaredpassenger]

the way your describing it, it sounds more like waste gate chatter (chirp chirp chirp noise)
as oppose to a dump valve which is a sudden heavy 'woosh' noise

are you sure they didnt have an after market wastegate on the turbo?

 

[indyjukebox]

I get this weird chirping from the left of the engine bay (when in the drivers seat) especially on acceleration, particularly in 5th and 6th gear. Is this waste gate chatter? I only noticed it after the Mountune upgrade and have so far been worried that something may be wrong with my car. However this is only when I accelerate. I have not noticed anything when backing off the throttle.

If thats what you want, then I would gladly swap it for silence as it is an irritating noise.

 

[Tall-Paul]

its still makes a dumpvalve noise but no chatter....amplified version (forge actuator)

Remapped st's make this noise with induction kits and remap however not as loud. Its the veins in the turbo chopping the compressed air inside the turbo when the dumpvalve has shut. My dumpvalve must be too slag and stay open a bit????

 

[RIK]

The sound you mean is when the presurised air from the turbo is stopped by the closed throttle butterfly and is then forced back through the turbo.

This noise is the air going back through the vains in the compressor housing. It is alot more noticable through on OPEN filter such as the DS induction unit !! A closed induction such as GGR etc.... muffles this sound and is less prominent !!!

Its not wastegate chatter.

 

[Tall-Paul]

QUOTE(RIK @ 14 Jan 2010, 07:35 PM) <{POST_SNAPBACK}>The sound you mean is when the presurised air from the turbo is stopped by the closed throttle butterfly and is then forced back through the turbo.

This noise is the air going back through the vains in the compressor housing. It is alot more noticable through on OPEN filter such as the DS induction unit !! A closed induction such as GGR etc.... muffles this sound and is less prominent !!!

Its not wastegate chatter.

Thats exactly it but mine doesnt make that noise. The only time it will though it when doing 78-80 and boot it in 6th....backing off when boost reaches max. You can hear it throught the passenger footwell but it sounds quite quiet and slow.

What could go wrong to not cause a chatter?

 

[MatST-3]

my car chatters with very little effert

but when i had a bump valve on the car it didnt do it

so i took the dump valve off and put a blanking plug in and the chatter started

i have the GGR cias and it does it with that.

but i will add that its not good for the turbo

but it does sound great

 

[RIK]

QUOTE(Tall-Paul @ 14 Jan 2010, 08:42 PM) <{POST_SNAPBACK}>Thats exactly it but mine doesnt make that noise. The only time it will though it when doing 78-80 and boot it in 6th....backing off when boost reaches max. You can hear it throught the passenger footwell but it sounds quite quiet and slow.

What could go wrong to not cause a chatter?

Possibly the dump valve not shutting fully. Some DV's dont work well on the

. Ive got the Blitz BOV on mine and its fine, as are most with the bailey one i beleive . Is there any fault codes to suggest a boost leak - pipe etc.... Are you sure its not right ???

QUOTE(MatST-3 @ 14 Jan 2010, 08:56 PM) <{POST_SNAPBACK}>my car chatters with very little effert

but when i had a bump valve on the car it didnt do it

so i took the dump valve off and put a blanking plug in and the chatter started

i have the GGR cias and it does it with that.

but i will add that its not good for the turbo

but it does sound great

The can hear it with the GGR but not very loud at all. More so at slow speeds !!

 

[Tall-Paul]

QUOTE(MatST-3 @ 14 Jan 2010, 07:56 PM) <{POST_SNAPBACK}>my car chatters with very little effert

but when i had a bump valve on the car it didnt do it

so i took the dump valve off and put a blanking plug in and the chatter started

i have the GGR cias and it does it with that.

but i will add that its not good for the turbo

but it does sound great

Yeh ive pulled out the vac hose on my dv which caused it to chatter, highly not recommended by dreamscience boys though!!! Im positive it will do it with a standard dv.

 

[Tall-Paul]

QUOTE(RIK @ 14 Jan 2010, 08:14 PM) <{POST_SNAPBACK}>Possibly the dump valve not shutting fully. Some DV's dont work well on the

. Ive got the Blitz BOV on mine and its fine, as are most with the bailey one i beleive . Is there any fault codes to suggest a boost leak - pipe etc.... Are you sure its not right ???

Im pretty sure its not right as even jared at dsci was surprised

Ive not scanned for faults but will do tomorrow...oh and its a standard dv which seems to be very easy to dump! The lowest of revs/boost will set if off when you back off, sometimes you can let half the throttle out and it will dump whilst still having a bit of power on

 

[gray]

are you on about the standard DV?

 

[Tall-Paul]

QUOTE(gray @ 15 Jan 2010, 12:19 AM) <{POST_SNAPBACK}>are you on about the standard DV?

In a way yes.....i have got a standard dv but the noise im talking about is turbo chatter

 

[RIK]

The std DV is built into the turbo itself. Its possible that the seal is faulty and is letting boost past it.

Is the boost holding @ 1.1 bar or is it struggling to make correct pressure ??
Has the boost solenoid been changed recently ?? - are the pipes re-fitted in the correct position?

Process of elimination im afraid mate !!!

 

[Tall-Paul]

QUOTE(RIK @ 15 Jan 2010, 08:43 PM) <{POST_SNAPBACK}>The std DV is built into the turbo itself. Its possible that the seal is faulty and is letting boost past it.

Is the boost holding @ 1.1 bar or is it struggling to make correct pressure ??
Has the boost solenoid been changed recently ?? - are the pipes re-fitted in the correct position?

Process of elimination im afraid mate !!!

As far as I know its never had the boost solenoid changed but i will give it a go if it might solve the problem.....are they expensive?

 

[RIK]

If its faulty mate it will either struggle to create boost or hit overboost in which the ecu will back the ignition off !!!

They are @ £30 i think - bin a while since i bought mine.......

What does the boost guage read / do ?? Does it drive smoothly????

Edit : - just reread your previous posts

...... the chatter you mean as i mentioned is the air backing through the turbo vanes when the butterfly is closed. HOWEVER - if you have a dump valve fitted - then the pressurised air is dumped through the DV preventing the air going back through the turbo !!!!
You would not hear any " chatter " as its not doing it as much if at all !!!!!!

A dv is generally fitted to prevent the air backing throught the turbo which in some instances causes compressor stall, which can damage / shatter the compressor in the turbo !!

Jared at dreamscience does not have a DV fitted mate !!!!!! - hence the reason why his is very noisy on the chatter front !!!!

 

[Jim G]

I got a dreamscience cais fitted yesterday and my turbo is chattering like a budjet

,i've got no aftermarket DV.

.

 

[MatST-3]

is there anyway of removing the standard DV?? as like i posted mine chatters but as to the reply its not that loud

 

[dan3d86]

Just out of interest, does it matter that much if it chatters?

As mentioned is it not bad for the turbo to be making this noise?

Or is it just because it sounds nice ?

I have the DSCI on mine and it sings all day long, im just wondering why its such an issue if it doesnt?

 

[MatST-3]

QUOTE(dan3d86 @ 17 Jan 2010, 11:51 AM) <{POST_SNAPBACK}>Just out of interest, does it matter that much if it chatters?

As mentioned is it not bad for the turbo to be making this noise?

Or is it just because it sounds nice ?

I have the DSCI on mine and it sings all day long, im just wondering why its such an issue if it doesnt?

personal choice i guess

it does sound great though

every1 knows the drawbacks of having the car do it.y spend 300quid to get the same noise when u can get the noise for free

 

[Funk]

Chatter sounds cool on a Group B rally monster. On a family hatchback it just sounds silly.