What is "Normal" in terms of Turbo Whine/Noise? Let's discuss.
06-07-2001, 01:13 PM
#11
Check my turbo noise recordings
The files that are named turbo-*
(WARNING, big files!)
Those were taken back in March, and as you know, the noise changes once in a while.
I noticed that when the siren noise gets worse (you can hear it EVEN when warm) it's cause the oil is a bit below the full mark, VERY fishy indeed.
Also, the new BPVs seemed to produce a bit more noise, probably cause they are not leaking like the old ones.
Once I am back home I will be getting more sounds and I'll post them so we can compare them.
.<ul><li><a href="http://server44.hypermart.net/fasts4andf4/">http://server44.hypermart.net/fasts4andf4/</a</li></ul>
(WARNING, big files!)
Those were taken back in March, and as you know, the noise changes once in a while.
I noticed that when the siren noise gets worse (you can hear it EVEN when warm) it's cause the oil is a bit below the full mark, VERY fishy indeed.
Also, the new BPVs seemed to produce a bit more noise, probably cause they are not leaking like the old ones.
Once I am back home I will be getting more sounds and I'll post them so we can compare them.
.<ul><li><a href="http://server44.hypermart.net/fasts4andf4/">http://server44.hypermart.net/fasts4andf4/</a</li></ul>
06-07-2001, 01:26 PM
#12
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I've never listened from outside the vehicle - but they are definitely loud!
I can hear the turbos over the A/C and reasonable radio volume. The noise is just a loud version of the normal spooling sounds - I guess some call it the siren sound.
I was just trying to point out that in my case the requested/actual boost track very closely, yet there is definitely something wrong.
Good luck on your MAF gremlin!
I was just trying to point out that in my case the requested/actual boost track very closely, yet there is definitely something wrong.
Good luck on your MAF gremlin!
06-07-2001, 01:28 PM
#14
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mm, your description of turbo noise is the best I've seen yet, ....
.... particularly the reference to the big rigs. It's the normal sound that is a clean "tone", without any raspyness, that increases pitch smoothly and goes beyond the audible range at full load. It's produced by the compressor blades. Anything that remains audible at WOT is something else. And, if it doesn't change pitch with turbo spool up, it's probably a leak.
06-07-2001, 01:41 PM
#19
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I agree in principle, but my experience is different ...
To my ears, my turbos make the same type of sound as when new - except that now the noise is much louder. The noise is apparent when the turbos begin to spool up, then becomes inaudible as the frequency increases. My suspicion is that this is caused by blade damage not unlike the pictures Nasa Racer has posted, but probably with less deformation.
I have logged block 115 and the boost values track very closely. The car will go under the knife soon and I will ask the tech to let me look at the turbos during the swap. Findings will be reported here.
I have logged block 115 and the boost values track very closely. The car will go under the knife soon and I will ask the tech to let me look at the turbos during the swap. Findings will be reported here.
06-07-2001, 01:43 PM
#20
From inside the engine.
Simply mounted a MIC under the hood, near the passenger's turbo, routed the wire around and then into the cabin (near the door hinge) and in to the digital recorder.
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