I haven't heard anything on my 3 cylinder.

 

quiet, smooth and lots of power

 

I have three turbocharged vehicles. I don't hear any turbo whine on the MINI or the Volvo, but my F350 with a 7.3 liter diesel does have some turbo whine, but the truck's turbocharger is close to the windshield and there isn't any sound insulation.

 

That, and the fact that the turbo is about as big as the Mini engine.

 

Heh, I work on turbochargers that are as big as the MINI!

They are on large slow speed diesels, 20,000 hp at 90 rpm, for example.
And there are two or three turbochargers per engine!

 

I can hear a faint whistle at times when I accelerate in my 2014 F56 manual hardtop. Is this something I should be concerned about? It has plenty of power and no codes.

 

Same, I can hear a faint whistle in sport mode - when accelerating hard (2014 F56 manual)

 

The intake is very quiet so you can't hear it.

Get an aftermarket intake and you'll hear the sweet turbo noises