Well, last night about 3am on 91 hwy heading west bound there was absolutely no traffic. I own a 1999 540 auto. They said that it's governed at 155*. Well, last night i actually whent pass the tach. It seemed like it read about a little pass 160. hard to tell because there where no more numbers. but, it's a pretty close guess. The car still seemed like it had plenty of Humph left in her. How is this possible.