Turbo Whine

[thewelsho]

Driving a Scooby offers a raft of wonderful audible experiences: the sound of that awesome flat four; the famed Scooby burble, and lets not forget some other choice sounds like BOVs and induction sounds. However, one of my favourites is when one hits 2k revs and the whine of a spooling turbo kicks in and gets higher and higher in pitch as the car gets faster and faster... a bit like a mini-jet enjine. However, what I can't fathom is that some days I hear it very clearly, yet other days its not quite so audible. Is it jsut me or is there an explanation for this?

JW

[plimpix]

Driving a Scooby offers a raft of wonderful audible experiences: the sound of that awesome flat four; the famed Scooby burble, and lets not forget some other choice sounds like BOVs and induction sounds. However, one of my favourites is when one hits 2k revs and the whine of a spooling turbo kicks in and gets higher and higher in pitch as the car gets faster and faster... a bit like a mini-jet enjine. However, what I can't fathom is that some days I hear it very clearly, yet other days its not quite so audible. Is it jsut me or is there an explanation for this?

JW

Would love to know this myself!

[scoob fae ork]

Could be down to the weather Ie cold damp air could make it louder i guess

[colin_ross]

New batteries in your hearing aid?

[RS Grant]

On warmer days, or after being stuck in traffic for a while.. the car isn't likely to hit the level of boost its meant to, so theoretically could be quieter and less aggressive on spool up as the ECU knocks things back a bit due to the higher ACTs?

Cheers,

Grant

[RA Dunk]

Is it jsut me or is there an explanation for this?

JW

alzheimer's

[davey l wrx]

I do believe it's down to the resonant frequency the turbo is spinning at. Same reason you can hear a jet engine spinning (the high pitched whining) when your stood in front or to the side of it but not from the rear (i know all the comments about being behind a jet engine are incoming but i don't mean right behind it). Once it's spinning at a certain speed it goes out of your hearing range. You notice it at airports when the aircraft taxi and turn the noise varies greatly.

I can usually hear the turbo my car up to about 4-4.5K then it goes quiet.

Edited March 30, 2009 by davey l wrx

[the blue dragon]

Driving a Scooby offers a raft of wonderful audible experiences: the sound of that awesome flat four; the famed Scooby burble, and lets not forget some other choice sounds like BOVs and induction sounds. However, one of my favourites is when one hits 2k revs and the whine of a spooling turbo kicks in and gets higher and higher in pitch as the car gets faster and faster... a bit like a mini-jet enjine. However, what I can't fathom is that some days I hear it very clearly, yet other days its not quite so audible. Is it jsut me or is there an explanation for this?

JW

Turn the music down John

Iain

[mystery machine]

Mine's exactly the same, John. Seems to be at its loudest when the air is cold and the car has had about five minutes to get halfway warmed-up. Other days, it's hardly noticeable. Didn't experience this with my previous turbo'd motor - it had a fairly consistent-sounding high-pitched whistle (distinct from the spin-cycle sound of the WRX turbo).

Also, mine doesn't boost totally consistently. Seems to need a few blasts on every drive before it begins to boost smoothly and fully - especially after a week of pottering back and forward to work. I'm told that this is 'ECU learning', but I'm yet to be fully convinced - I do get a fair bit of 'wastegate chatter' (or 'boost solenoid ticking' - not exactly sure of the source). I always wait until it's warmed up before I give it a proper belt, BTW.

[oletam]

Also, mine doesn't boost totally consistently. Seems to need a few blasts on every drive before it begins to boost smoothly and fully - especially after a week of pottering back and forward to work. I'm told that this is 'ECU learning', but I'm yet to be fully convinced - I do get a fair bit of 'wastegate chatter' (or 'boost solenoid ticking' - not exactly sure of the source).

I had something similar on mine. Turned out to be the heat shields rattling. Removed them and heat wrapped the pipe. problem solved

[thewelsho]

Oh hahaha! I'm splitting ma sides at a' the funny guys! I'm going with the idea that it has something to do with the air type; either its density or temperature, or other factors, or all of that! In other words, I dunno! But at least others have experienced the same phenomenon... wooo big word to describe a noise - Anyway, I'll jsut enjoy when its there and when its not I won't let it concern me!