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Just a query really. I have an EA82Turbo in a brumby and the turbo seems to be really noisy. Not a bearing noise or anything, but just the sound of the air spooling. My son has an RX7 with a 13b turbo and you can't really hear anything until the wastgate blows.

Is this normal for the EA82T...I'm getting about 10psi of boost and the car performs pretty good so I'm sure its not a leak. Gets a bit annoying when you're cruising down the highway and any variance in throttle, all you can hear is the hissing of the air going up and down, even at high speed. Didn't think you would hear anything...,

mine does this esp coz of the big pod filter. im having some other weird turbo noises tho also ! again haha

G'day mate, do you run an intercooler? if so could one of the pipes be leaking? Cheers Ethan

It depends what you have before the turbo

If you have a pod filter, it will be really noisy, if you have the factory airbox/filter, it will be a bit quieter and if you have the factory airbox and the resonator/snorkel thingy in the quarter panel, it will be barely noticeable

Thanks for all this...I'll check all hoses. It does have an intercooler on top. Filter is foam pod type I guess sitting in the old battery area. When you rev it idling in the garage without load, you can't hear it. Out on the highway and about town under load, it is very noticeable and a bit annoying. Its a loud hissing noise.

You talking about induction noise?
If you use a more restrictive air filter assembly like the factory setup it will be quieter. You'll also lose some performance.

It's quite simple to test a std airbox system to see if it's doing a good job .

You need to measure the pressure in a std airbox on the engine side of the element , if its airflow is inadequate it forms a restriction and the pressure drops downstream of the element .

My other ride is a 96 R33 Skyline GTS25T and these have quite a reasonable airbox for the 185Kw they're supposed to make .
All the young heroes throw pod filters on them which makes them noisy (as you know) and they take in hot post radiator air from the engine bay .
The people I know say that these and the later R34 version have good inlet system and that its mainly the paper element filter that gives a bit of restriction .
Pipercross in England make effective filter elements and the one I bought from Faber/Midel (The SU Carb specialists in Sydney) made a noticeable difference in this case , the cars std boost gauge rises to atmospheric faster at low revs than it used to and it feels a little more lively .

Bottom line in my book is that if you can make a production airbox work and its quiet why not .
Also the std EA82MPFI filter element is almost the same as the Nissan one my DR30 turbo Skyline had and it was good for ~ 147Kw . Some mug possibly in Japan decided to cut the roof off the airboxes steel lid and it made a bit of compressor noise which the std cars didn't .

Cheers A .