Mines there 247, no matter hot\cold, 87-89-91 octane....
-I dont recall mine doing it til I got in an accident, and oil was leaking badly from a broken hose on the pass side of the engine bay at the front.
-I had the stock hood before, now I have a cf with reverse cowl
-My friends makes a similar sound, but with his hood down, you cant hear it unless you ReAlly try to.
Maybe I am just hearing it more because the CF isnt as dense and has the vent... but I dont recall ever hearing it when I rev'd it with the hood up either. Oh well the dealer didnt seem to think it was anything that would hurt the car, they assured me it would be fine. IF my engine does decide to blow it better be in the next 10k or I am really screwd.