Ok I was going to watch a football game up at the high school last night. The road to the school is a great with lots of twisties.(there is even a pretty nice corkscrew!
) So I was on my way and the M50 was starting it's typical 3500rpm roar, then at about 4000rpm I hear a slight whistling like sound, almost like a supercharger turning. I tried to get it to do it again today but it only did it once for about three secs. Any ideas on what the sound is? Maybe I just never caught the sound before or maybe I'm just a little paranoid. Thanks guys.
Edit: It didn't sound like a supercharger spinning, just the increased airflow from it.....you know what I'm talking about, I can't think right now.