Or it was a 1998, as that's in the ballpark of the output of BMW's pre-2001 3.2L They don't have the redline (or the engine durability headaches) of the newer 330hp 3.2L M3's, but they were reasonably quick too with strong mid-range torque.

It's not the window being down. I have the convertable. Top up or top down, there's no appreciable acceleration difference at loess than triple digit speeds. But if it was a really hot night, you were likely down a little on power even if the IC pump was working correctly. That's just the reality of driving a boosted vehicle.