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Ok

well this noise has been there since the day I picked up my car which should be going into its 3rd month now and the car was bought of a former forum member who told me everything about the car so I was happy with it and still am.

BUT

I have heard skylines go flying past me at full WOOT and the noise my turbo makes is no where near to what theirs makes.

I get a really scratchy, whiney supercharger kinda noise and I don't think im losing any boost coz my boost gauge (after market Apexi gauge) on full throttle is reading just over 0.5bar which I take it is around 8psi.

The only mods are a pod filter and cat back exhaust.

The noise only starts when it's past 4500 or when the second stage boost kicks in and boosts to 7-8psi.

Now I also have searched through the forums and have read to check for leaks in cooler and intake piping. But also read some where the could be leaking gasket.

If it's the gasket would the exhaust note sound a shit load louder also? Car sounds normal for a RB25DET with 3" from the cat.

Any ideas?

Would shaft play cause a noise like this? Im not getting ticking, clunking, rubbing noises just a really high pitch scratchy supercharger kinda noise.

Your help will be greatly appreciated

Thanks

Ash

Can you describe the noise?

my car made a real screaming noise when i boosted it and it turned out to be a leaking exhaust manifold gasket aswell as turbo inlet gasket.

If thats the case it wont cost much to repair.

If its a leaking gasket you can try this;

Good trick to test a leaking gasket is to get a thick cloth or rag.

Start the car and let it idle, then get someone to hold the cloth/rag over the exahaust, blocking it completely for a few seconds while someone sticks there head in the engine bay on the turbo side and listens for any exhaust leaks!

What it does it builds up the pressure in the exhaust, and it leaks out from the weakest point (gasket leak).

Try that, if you have trouble man, I will check it for you on the weekend when I pick up the wheels.

My cousins a mechanic also so I will get him to look at it also for a 2nd opinion, as he will be with me more than likely.

Edited by abu
Can you describe the noise?

my car made a real screaming noise when i boosted it and it turned out to be a leaking exhaust manifold gasket aswell as turbo inlet gasket.

If thats the case it wont cost much to repair.

exactly what you said. it comes on as a normall spool noise then screams like a mofo. duno if you have heard a supercharger before but sounds like a scratchy charger.

god i hope its only those gaskets.

any idea on cost?

If its a leaking gasket you can try this;

Good trick to test a leaking gasket is to get a thick cloth or rag.

Start the car and let it idle, then get someone to hold the cloth/rag over the exahaust, blocking it completely for a few seconds while someone sticks there head in the engine bay on the turbo side and listens for any exhaust leaks!

What it does it builds up the pressure in the exhaust, and it leaks out from the weakest point (gasket leak).

Try that, if you have trouble man, I will check it for you on the weekend when I pick up the wheels.

My cousins a mechanic also so I will get him to look at it also for a 2nd opinion, as he will be with me more than likely.

dude if you will be able tog et that done that will be ace. i can bring the wheels to you

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