Audi RS 5 Cylinder

[Turkish]

 

[kpowell911]

Wastegate Chatter FTW

 

[Gally]

Flol! Some of those noises!

 

[couzens]

Saw this at Le Mans on the Audi stand, It's as epic in the flesh as it is on screen

 

[deanogee7]

this is car p**n! love the 5 cylinder engine

 

[Addicted]

Awesome, that wastegate chatter!

 

[Ian_182]

Awsome noises.

 

[MaLicE]

No such thing as "waste gate chatter" if ur waste gate is making a noise... There is an issue... What you are all calling waste gate chatter is compressor surge.

 

[Eddie.]

Fantastic noises. Looks tremendous too.

 

[Merk]

No such thing as "waste gate chatter" if ur waste gate is making a noise... There is an issue... What you are all calling waste gate chatter is compressor surge.

You are so cool right now.

 

[Pete.M]

No such thing as "waste gate chatter" if ur waste gate is making a noise... There is an issue... What you are all calling waste gate chatter is compressor surge.

Indeed we were at the gold cup at oulton at the weekend and the commentator on the rally/drift track was calling it waste gate chatter which was annoying my mate who was heavily into Renault 5 turbos and knows a lot about cars.

For those who don't know this is an interesting read...From wiki

There is confusion in the automotive world about so called "wastegate chatter" or "turbo flutter". A noise created on lifting off the throttle in a turbocharged car, commonly described as a chipmunk or a rattlesnake, is often stated incorrectly as being a result of the turbo's wastegate closing.
The noise is in fact the air compressed by the turbo passing back through the compressor wheel of the turbo after the airflow is abruptly halted by the throttle plate closing, called compressor surge. However, in some cases, i.e. where the throttle plate doesn't open fast enough or is set up to only react to high boost, some chatter will remain. Surge can occur on diesels when the turbo is attempting to pressurize the air at a higher pressure ratio than the compressor wheel can flow at a given speed. Most Diesel engines have no use for ablow off valve as they do not have a throttle plate.
The chatter noise is very noticeable on World Rally Cars, where anti-lag is used.
A compressor stall like this can cause excess stress and wear on the turbo's shaft or bearings under higher load applications of the turbo (around 15 psi (1.00 bar) and greater depending on the trim and flow rate of the compressor side).
Actual wastegate flutter occurs instead under partial boost conditions such as partial throttle near the boost threshold. It sounds like FftFftFftFft not ShuShuShushu and is caused by the rapid opening and closing of the wastegate at boost levels near the spring pressure. It is commonly heard more clearly and may be more prominent on cars with modified intake silencers, up-pipes, downpipes, or an oversized wastegate incorrectly matched to that specific engine. Also, vehicles using on/off solenoids to control boost can do this under certain conditions. It is not harmful to the engine. Some may claim that it can damage the wastegate, which may be possible under some circumstances, however some vehicles flutter regularly inherently from the factory without any consequence.

 

[Laine_16v]

Wastegate chatter FTW!

 

[pastieman]

That's why i loved it in my fiesta turbo

http://youtu.be/baUEBAKw5vQ

Not my video tho

 

[Eddie.]

There is confusion in the automotive world about so called "wastegate chatter" or "turbo flutter". A noise created on lifting off the throttle in a turbocharged car, commonly described as a chipmunk or a rattlesnake, is often stated incorrectly as being a result of the turbo's wastegate closing.
The noise is in fact the air compressed by the turbo passing back through the compressor wheel of the turbo after the airflow is abruptly halted by the throttle plate closing, called compressor surge. However, in some cases, i.e. where the throttle plate doesn't open fast enough or is set up to only react to high boost, some chatter will remain. Surge can occur on diesels when the turbo is attempting to pressurize the air at a higher pressure ratio than the compressor wheel can flow at a given speed. Most Diesel engines have no use for ablow off valve as they do not have a throttle plate.
The chatter noise is very noticeable on World Rally Cars, where anti-lag is used.
A compressor stall like this can cause excess stress and wear on the turbo's shaft or bearings under higher load applications of the turbo (around 15 psi (1.00 bar) and greater depending on the trim and flow rate of the compressor side).
Actual wastegate flutter occurs instead under partial boost conditions such as partial throttle near the boost threshold. It sounds like FftFftFftFft not ShuShuShushu and is caused by the rapid opening and closing of the wastegate at boost levels near the spring pressure. It is commonly heard more clearly and may be more prominent on cars with modified intake silencers, up-pipes, downpipes, or an oversized wastegate incorrectly matched to that specific engine. Also, vehicles using on/off solenoids to control boost can do this under certain conditions. It is not harmful to the engine. Some may claim that it can damage the wastegate, which may be possible under some circumstances, however some vehicles flutter regularly inherently from the factory without any consequence.

That's a properly interesting read about wastegate chatter.