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Old 04-18-2016, 02:30 PM   #20 (permalink)
Frank Lee
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Join Date: Jan 2008
Location: up north
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Blue - '93 Ford Tempo
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Quote:
Originally Posted by serialk11r View Post
A lot of you are mentioning "torque band", but that's totally missing the point. What we actually care about is efficiency band, not torque band, and more gears helps put you there faster. If a shift drops you from 2500 to 1600, the engine is quite a bit less efficient than if the transmission could keep the revs above 2000, during acceleration.

If you're going >50mph, then you're probably in the tallest gear, but what about 45? Or 35? Or 40? If at 40mph you have to shift into 5th gear in a 6 speed, that could mean running the engine 60% faster with wide spacing, and losing 20% fuel economy. An 8 speed avoids that by having 2 gears closer together in that range.
Just go fast enough to pull top gear. Done.

Engines having broad flat torque curves thus having a larger useful rpm range + vast multitudes of ratios is missing the point?

Efficiency band while accelerating? And accelerating lasts how long- a few seconds. Cruising along lasts how long- exponentially longer- could be hours. Put that thing in the efficiency zone when at cruise speed.
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