[epbrown]

When it comes to improving 0-60 times, it pays to pay less attention to horsepower and check to see if the car maker changed the gearing or improved torque numbers - that tends to be where they make their acceleration gains. In the case of the 2005 3.0i over the 2006 3.0si, I think BMW went from a 3.07 final drive to a 3.23 (3.46 for the coupe). Buy the 2005 3.0i and spend $400 on a 3.46 rear end, you're back in the game.

Similar effect with the E46 M3 compared to the E90 M3 - while the 30ft-lbs they added helps the car off the line, they also changed from a 3.62 final drive to a 3.85. Add in the fact the new car weghs more, and you can see why swapping a 3.91 or 4.10 final drive would make the E46 fast enough for you to not be able to tell the difference without instruments.

As for the E46 M3's times. Factory quoted figure was 5sec for 0-60, most magazines got 4.7sec. The new M3 is quoted at 4.7sec by BMW, most mags get 4.4sec.