Quote:
Originally Posted by Jordo!
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Moreover, the gearing ratios are very good, very close, and similar to those for MT, although needing an extra gear to achieve it.
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Actually, I've just recently been staring at all the related numbers, and the ratios are quite different between the two:
7AT: 4.924, 3.194, 2.043, 1.412, 1.000, 0.862, 0.772 w/ 3.357 final drive
6MT: 3.794, 2.324, 1.624, 1.271, 1.000, 0.794 w/ 3.692 final drive
If you go ahead and multiply out for the final drive difference, you can see that the 7AT has a wider range on both ends; the low gears are even lower than the 6MT, and the high gears are higher:
7AT: 16.530, 10.722, 6.858, 4.740, 3.357, 2.894, 2.592
6MT: 14.007, 8.580, 5.996, 4.693, 3.692, 2.931
However, the percentage change in ratios between successive gears looks like this:
7AT: 35.1% -> 36.0% -> 30.9% -> 29.2% -> 13.8% -> 10.4%
6MT: 38.7% -> 30.1% -> 21.7% -> 21.3% -> 20.6%
Which means the 6MT has narrower gearing in the middle gears that you care most about (3->4->5), which keeps you in the powerband easier. The 7AT has wider gears at the bottom/middle, but then significantly narrower way out at the top (which is useless for anything but high-mpg cruising, unless you drop in a very very different final drive gear).