I just had a 15% pulley installed this weekend (a pulley party) and I am not sure I have a problem or just having jitters.

Let me make sure to be clear, I appreciate the installer's efforts and giving back to the MINI community what he can by using skills he has. I never would have attempted this by myself and no way I could afford the $3-400 to have it installed at a shop.

Ok. After any major change to my cars I have always been "hyper aware". I seem to notice everything, whereas before hand I might not have paid attention to it. What I am experiencing (or think I am) is an increased vibration that I feel through the gas pedal. Also, a new noise. Not the whine of the supercharger. This sounds more like tire noise or perhaps a belt noise.

The noise sounds like a hum that varies in pitch every couple secounds. Repeated, not random.

Any ideas? Am I just crazy?