WasteGate Chatter
10 August 2006, 03:02 PM
#61
Scooby Regular
Join Date: Sep 2000
Location: Notts, UK
Posts: 4,935
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Mike Rainbird
I disagree. The standard boost pressures that these turbos run from the factory, is not sufficent to cause the shock loads you mention. IMO, it is PURELY for noise suppression. I have NEVER EVER seen a turbo fail without a dumpvalve, running factory boost.
What is certain is running a turbine in a stall condition adds strain and fatigue, whether this takes 1000miles off it's life or 30000miles off it's life is very hard to quantify and depends on the specific use and design.
I would almost certainly say that most manufacturers fit a DV for relaibility reasons as well as noise suppresion though.
Cheers
Lee
10 August 2006, 03:33 PM
#62
Scooby Regular
Join Date: Jan 2006
Location: London
Posts: 52
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by GC8
It shows; now run along.
10 August 2006, 09:48 PM
#64
Scooby Regular
Join Date: Aug 2005
Posts: 198
Likes: 0
Received 0 Likes
on
0 Posts
I have read quite a few types of posts where people ask how to make their Scoob sound like a WRC ie the chirps etc.. As some one has already mentioned it is not an external wastegate on them either but surge, My old pulsar with a KN cone and a VTA used to sound pretty similar sounded kinda cool.
Any way so how do you block off the DV then? I take it you just put a blanking plate on the intercooler, do you make said item or order it from some where, I also take it you would have to have a cone filter on to amplyfy the noise?
Any way so how do you block off the DV then? I take it you just put a blanking plate on the intercooler, do you make said item or order it from some where, I also take it you would have to have a cone filter on to amplyfy the noise?
10 August 2006, 10:05 PM
#65
Scooby Regular
Join Date: Aug 2005
Posts: 198
Likes: 0
Received 0 Likes
on
0 Posts
Just to really clear things up found this, a vid of a Scoob with an external wastegate.
http://www.youtube.com/watch?v=8dMC1rvf9IQ
http://www.youtube.com/watch?v=8dMC1rvf9IQ
20 December 2006, 07:19 PM
#67
Scooby Regular
Thread Starter
Join Date: Jun 2006
Location: Norwich
Posts: 1,526
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Bat-Fink
WRC cars run ALS as well
A normal re-circ DV does not make any noise as you know.
A VTA one does make a ptshhh noise.
Nissan Silvia S13 CA18DET Aftermarket Blow-off Valve (BOV) - Google Video
But if you blank off the dv hole,when you close the throttle what happens is the air hits the now closed throttle plate and travels back towards the compressor wheel on the turbo.
The air gets chopped up by the spinning compressor wheel and thus makes a very cool noise.
This is called comp stall or comp surge.
NOT! wastegate chatter.
A example of comp surge.
http://video.google.co.uk/videoplay?...4393&q=chatter
Another good example of running without a DV,even tho it says it's got a DV it ain't
YouTube - S15 BOV
Dan.
Last edited by Bat-Fink; 20 December 2006 at 07:24 PM.
20 December 2006, 07:21 PM
#68
Scooby Regular
Join Date: Aug 2004
Location: Land of Reflection
Posts: 911
Likes: 0
Received 0 Likes
on
0 Posts
Yer ive regularly been at events where ppl have commented on comp surge hmmm not saying theyre wrong buts lets face it most ppl know it as wastegate chatter
20 December 2006, 07:26 PM
#70
Scooby Regular
Thread Starter
Join Date: Jun 2006
Location: Norwich
Posts: 1,526
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by ukdave
Yer ive regularly been at events where ppl have commented on comp surge hmmm not saying theyre wrong buts lets face it most ppl know it as wastegate chatter
20 December 2006, 07:30 PM
#72
Scooby Regular
Thread Starter
Join Date: Jun 2006
Location: Norwich
Posts: 1,526
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by ukdave
lol i know but its what its mainly referred to as 
pmsl cant believe we`ve opened this old thread about it-im blaming u 
pmsl cant believe we`ve opened this old thread about it-im blaming u 
21 December 2006, 12:48 PM
#74
Scooby Regular
Join Date: Mar 2002
Location: Bradford
Posts: 13,720
Likes: 0
Received 0 Likes
on
0 Posts
Logic Check
I used to get that chattering noise when lifting at medium boost and medium engine speeds in my MY99. I was using a Forge VTA dumpvalve at the time and running 1.2bar of boost on the TD04. Lifting from full boost and/or full chat would produce the 'Tisssssssh' we expect of a VTA. Lifting at very low boost might produce a little hiss but mid-way would give you that chatter.
Based on what I've read in this thread it is my understanding that:
* When I was closing the throttle at high boost the excess air was backing up and blowing off out the DV into the atmosphere. No problems there (aside from borewash and other related issues with VTA on scooby).
* When I was lifting off at medium boost the air was backing up but wasn't at a sufficient pressure to overcome the DV spring and so would travel back and stall the turbo, hence the chatter.
^^^ are both of those accurate? Is it fair to say the chatter could have been reduced/eliminated by a weaker DV spring? Would that chatter have been harmful to the turbo?
I used to get that chattering noise when lifting at medium boost and medium engine speeds in my MY99. I was using a Forge VTA dumpvalve at the time and running 1.2bar of boost on the TD04. Lifting from full boost and/or full chat would produce the 'Tisssssssh' we expect of a VTA. Lifting at very low boost might produce a little hiss but mid-way would give you that chatter.
Based on what I've read in this thread it is my understanding that:
* When I was closing the throttle at high boost the excess air was backing up and blowing off out the DV into the atmosphere. No problems there (aside from borewash and other related issues with VTA on scooby).
* When I was lifting off at medium boost the air was backing up but wasn't at a sufficient pressure to overcome the DV spring and so would travel back and stall the turbo, hence the chatter.
^^^ are both of those accurate? Is it fair to say the chatter could have been reduced/eliminated by a weaker DV spring? Would that chatter have been harmful to the turbo?
21 December 2006, 12:52 PM
#76
Scooby Regular
Thread Starter
Join Date: Jun 2006
Location: Norwich
Posts: 1,526
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by Saxo Boy
Logic Check
I used to get that chattering noise when lifting at medium boost and medium engine speeds in my MY99. I was using a Forge VTA dumpvalve at the time and running 1.2bar of boost on the TD04. Lifting from full boost and/or full chat would produce the 'Tisssssssh' we expect of a VTA. Lifting at very low boost might produce a little hiss but mid-way would give you that chatter.
Based on what I've read in this thread it is my understanding that:
* When I was closing the throttle at high boost the excess air was backing up and blowing off out the DV into the atmosphere. No problems there (aside from borewash and other related issues with VTA on scooby).
* When I was lifting off at medium boost the air was backing up but wasn't at a sufficient pressure to overcome the DV spring and so would travel back and stall the turbo, hence the chatter.
^^^ are both of those accurate? Is it fair to say the chatter could have been reduced/eliminated by a weaker DV spring? Would that chatter have been harmful to the turbo?
I used to get that chattering noise when lifting at medium boost and medium engine speeds in my MY99. I was using a Forge VTA dumpvalve at the time and running 1.2bar of boost on the TD04. Lifting from full boost and/or full chat would produce the 'Tisssssssh' we expect of a VTA. Lifting at very low boost might produce a little hiss but mid-way would give you that chatter.
Based on what I've read in this thread it is my understanding that:
* When I was closing the throttle at high boost the excess air was backing up and blowing off out the DV into the atmosphere. No problems there (aside from borewash and other related issues with VTA on scooby).
* When I was lifting off at medium boost the air was backing up but wasn't at a sufficient pressure to overcome the DV spring and so would travel back and stall the turbo, hence the chatter.
^^^ are both of those accurate? Is it fair to say the chatter could have been reduced/eliminated by a weaker DV spring? Would that chatter have been harmful to the turbo?
Not sure on turbo strength as you never hear on here about how strong the turbos are against it.
Thread
Thread Starter
Forum
Replies
Last Post
aaron_ions
General Technical
14
25 September 2015 02:33 PM
