What is a Turbo whistle?
Turbo whistle is the sound of the compressor inside the turbocharger speeding up (also known as 'spooling up', which is why it kicks in at the boost threshold (when the turbo starts to kick in) as you accelerate up the rev range.
Does the turbo whistle work?
It works. It doesn't blow off, all it does is whistle, but it works. MAKE SURE you read the measurements on this thing before you buy. I bought it and ended up having to do alot of work trying to get a good enough flow for it to work because my aftermarket muffler was way too big.
Is it normal to hear turbo whistle?
A "turbo whistle" usually indicates a worn and failing turbo bearing, which is pretty much all there is to go wrong with a turbo.
Are whistle tips illegal?
Whistle Tips
These aren't exactly new, but they were recently popularized by a KRON-TV interview with Oakland resident Bubb Rubb and his imitation of the whistle tip screeching. Regardless, these devices are illegal in California