It's been two months that I own my 91 3.6 M5. I'm not sure if I'm getting used to the car or if it's a little slower (less torque) less acceleration... I've been hearing a sound of some belt squeaking when revs are high even when the ac is off. At the end of third gear I'm around 100 mph (that hasn't changed since i've bought it). Am I getting crazy or there's something wrong with my car??? thank you.