My MY00 Euro/UK spec turbo has made the police/fire siren faint sound at those revs, 2500 to 2800, from brand new mainly from cold and even at normal temps, but not always. Sometimes it's more noticeable than other times. When I first heard it, basically the first time I drove it, I was looking in the rear view mirror to see if an emergency vehicle was coming, so I could move out of it's way. It sounded far away. I then realised it was the car. 13000 miles later, it still does it and there has been no problems. I never really worried about it. I just thought it was normal. Sometimes when I can't hear it I think something is wrong. This is the first time I have heard of anyone else mentioning it.

Mine does not have the standard exhaust system. The car made the noise when the car was standard and it still does it with quite a few mods, exhaust, cold air induction, electronic boost controller, blow off valve, etc. No roller bearing turbos on the MY99/00 euro spec cars either.

When Beastie (scoobynet member) was over here for holidays last year, I took him for a wrap in my car and I asked him if he could hear the faint sound. When I told him it sounded like a police siren, that's when he heard it, cos he knew what to listen for. We concluded it was just normal. Maybe something to do with the turbo blades?
Cheers,

Wrexy.