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Discussion Starter · #1 ·
Right, i may sound like a real new fish here (or a tosser), but the noise that comes out the back of a turbo car, i.e. like a woosh, ive heard some sound like a bloody jet! somtimes its so loud, it sounds like summats scraping! (hard to explain) what is it that makes this noise? Ive been told an uprated exhaust.... Maybe an inducton kit (more air)? ...someone mentioned the wastegate??

Basically i think uprated exhausts make it but, is the noise the cat restricting the gases? or a decat where all the gases are just being forced out. ive heard this noise on astra turbos, focus st, evos etc even a standard megane sport,

cheers, joN
 

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The woosh sound you hear comes from the diverter/dump valve and not
the exhaust. You shouldn`t be getting any sounds like that from
the exhaust.
 

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i know what you mean mate. my mates pulsar and skyline makes that noise. its like a roar. they have over 400bhp so thatwould explain that. minehas a the same effect but no where near as loud. iv got a2 1/2" exhaust and decat if that helps. butif you run ALOT of boost it would make that noise not sure on golfs though never really been around a high power golf.

hth
 

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i know what you mean mate. my mates pulsar and skyline makes that noise. its like a roar. they have over 400bhp so thatwould explain that. minehas a the same effect but no where near as loud. iv got a2 1/2" exhaust and decat if that helps. butif you run ALOT of boost it would make that noise not sure on golfs though never really been around a high power golf. its also thenoise of the tyres tryin there hardest to grip...

hth
 

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The woosh sound you hear comes from the diverter/dump valve and not the exhaust. You shouldn`t be getting any sounds like that from the exhaust.
No the diverter valve doesn't make all that much noise at all. What you need to buy is a Cold Air Induction kit like the Carbonia. That is what makes the load whoosh on the MK4 turbos.
 

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Discussion Starter · #9 ·
Good stuff, i thought this about the carbonio, (the more air idea) im after one at the minute. suppose is it the combination of both? the induction kit and exhaust?

joN
 

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thats what mine sounds like mate.not far from that.its gona be mean when running more boost in a big turbo....cant wait till the end of the year :D
 

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Discussion Starter · #12 ·
Its only slight on that green one, which is suprising as its 302bhp, and the ibiza is only very mildly tuned. must be just the type/style of the exhaust, does this mean you lose this noise if you decat/race cat it?

joN
 

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Discussion Starter · #13 ·
If anyone is bothered, lol I know know how to get this noise, I have it now with my standard exhaust, its when you get a remap, hence higher boost. the noise is the boost trying to get through your cat, becuase when the cat is removed, the noise goes. If you uprate your exhaust it goes louder, like in the ibiza clip.

thankyou,the end.lol
 

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it is nothing to do with cat it is just simply the high speed exhaust gasses flying through the pipe and the turbine blades of the exhaust side of the turbo
 

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it is nothing to do with cat it is just simply the high speed exhaust gasses flying through the pipe and the turbine blades of the exhaust side of the turbo
dito...

i have no cat and have that noise when i go for it. its all about how much boost you have going through the turbo and thats the gases coming out....
 

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no it is not, he means the one off a normal internal wastegate turbo but what you called a screamer pipe in real world called a wastegate exhaust pipe does make that noise REAL loud yes
 

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Discussion Starter · #18 ·
Its funny how no-one was bothered about this when I wanted to know, but now they are. this noise became apparent on my car when I got a remap.and I know of a person with the same engine, has a decat and his doesnt make this noise, so i just put 2+2 together.

I was just guessing.

joN
 
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