That whistle is from the Blow Off Valve... Love that sound.

Stock engines don't typically have blow-off valves, they have wastegates. The whistle is the turbo.

There's an active member who has an ESS supercharger on his 4.6is. Pull up some of his old posts - he has some detailed information.

ESS4.6is

NOthing beats the sound of twin turbos spooling!! I miss my twin turbo set-up.:)

Did Sharka uninstall his turbo before he sold it? The main reason I want to go to the CT meet is to see your car. :)

heh...sounds cool,
actually he didnt get around to installing it, although he was about to, the intercooler was mounted in front, but im considering the ess charger this summer.

i actually seen someone take a ess charged 4.4 engine and place it in a m3, because they said it would leave more room to produce more power than the m5 would have.