turbo chatter

[30psi]

You need an aftermarket air filter, as a standard one will suppress the noise.

Turbo chatter is when the volume of compressed air forces its way back through the turbo (the wrong way). The turbo slows down loads when this happens and the noise is the chopping of the air coming back out.

On the standard pipe from turbo to throttle body there is very little volume there so the sound is hardly audible as there isnt much air to go back through the turbo. If you intercool it you are multiplying the volume and then you'll get a good chatter. The larger the turbo the better the longer the chatter lasts. This actually causes harm to the turbo by stressing the shaft as it slows down and may even almost go backwards. The reason why a dumpvalve is used is to reduce the back pressure on the turbo and therefore reducing the stress on it. Ideally you want a dump valve that only goes off on full boost, so an adjustable on is ideal, as I personally don't like the essex sound of a dump valve.