I have an STi V Type R - and I have a question - can you hear your turbo spin up at around 3.5k revs thru to 4k ish - quiet whistling type of sound - don't think it is the Blow off valve problem - could just be me being over sensitive to noise and therefore not being used to turbo engines just not used to hearing it.

STi V 4-door:

Yep, can hear the turbo above about 3000 rpm, up to about 4500 rpm. After that, I thjink its drowned out by the engine...

I can hear my turbo spin up from about 2000rpm (with the stereo off of course!).

MY98 Turbo

Neil.

Hmmm well I can hear two distinct types of sound. One under hard acceleration from about 3k - 4.5k there is a light but audible whistling - not a gernerator type whirring. Having looked at the FAQ i worry(probably too much) that it might be the Blow off valve thingy as I said earlier - but it is only a light whistle.

If it only happens on acceleration it should be the turbo spin-up. The sound is very quiet & it's easy to miss. I couldn't hear it on my 99my for about a month after I got it. I have yet to hear the spin-down sound.
The STi may have a slightly bigger turbo in which case the sound may be a slightly lower note of whistle.

Immediately after the spin-up you should notice that your engine is more powerful ie on-boost.

After discussion with Pete Croney - wish we had had the time on Saturdday for him to come for a run - we suspect the dump valve is leaking a little. He has said he has had another STi V with similair problem - but the part is standard to the 99My and is only a 5 min job - so when i get the chance......we will try and get it done. I really don't think it is the turbo I hear as it doesn't sound turbiney if you know what I mean.

Interesting, that. i was going to ask around.

I have an STI V, and since about 2000 miles it does exactly that - there is a whistling, "cammy" type sound from about 3500 revs all the way up. SOunds like a very tight belt, but it's not - and it's not linked to rpm. Interestingly, I only hear it after I've given the car some -er- exercise of the major rev variety for 15 mins or more. If I pootle around, let it warm up, and then floor it, it doesn't happen - so I presume it's temp sensitive. let the thing cool down, and it gradually goes. Is this the same thing? Certainly the car goes too fast whether or not I can hear it. Is it about to do something awful, I ask myself? advice from professional scooby owners gratefully taken.

Nope sounds unrelated to the problem I am having.