ReflectingGod wrote:The problem with the argument on ratios is that there are a limited number of gears in a car (typically 5/6 in a modern manual, and 4/5 in an automatic). First gear has to be tall enough to launch easily, and you don't want huge gaps between ratios, so you can't neccesarily put in a gear as high as you want.
The intersting thing about automatic transmissions is that the ratios can also be controlled by the amount of liquid in the turbines. The liquid which gets a spin directly from the turbine which is connected to the engine output shaft than rotates a turbine which is connected to all the gear stuff. If you have little liquid that spins the turbine you get the same effect as a small wheel that rotates a large wheel. The result is extra trouqe but this realy puts the strain on the turbine system... So while the loss of power in automatic transmissions is a weakness, the flexability of gears is a great feature. This is exactly why modern cars can have only 4 gears that'll get them all the way to over 100mph while still having very reasonable accelerations.