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Old 06-23-2011, 01:49 PM   #41
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Originally Posted by CoasterDan View Post
This wouldn't be necessary with a traditional auto. trans because the torque converter would allow the revs to come up for more power in the higher gear.
The shift changes in a conventional automatic are determined by the transmission control unit (TCU), just as they are for the DCT (PowerShift). Both transmissions take input from a similar set of sources. For best fuel economy, which seems to be super important for this vehicle class, Ford has programmed the shift changes to occur at a low rpm, around 1500 - 2000 rpm in standard drive mode, in my experience.

Originally Posted by RustySocket View Post
A typical auto with a torque converter will typically shift very smooth and has a smooth power delivery to the wheels, essentially because the converter slips and does not lockup initially.

A manual is slipped by the driver and lockup occurs as soon as the clutch pedal is released. When driving a manual about the only time you really slip the clutch is when leaving in first gear. Once the car is moving most drivers rev it out and then shift at about the same RPM until up to speed.

I like to drive in sport mode and rev the car out a little bit and then also downshift into corners to use engine braking as well. In drive or with a standard auto you cannot do this.
Agreed. For a manual or DCT to have smooth up shifts, the shift must be timed with the vehicle speed and engine rpm, assuming the driver isn't going to do something else during the shift, like sudden hard braking. Typically, on a manual, the throttle is let up briefly when the clutch is disengaged to keep the rpm's in check, but the resulting hesitation can be felt by the driver.

From this article describing the PowerShift:

Ford PowerShift’s advanced features include:

Torque Hole Fill: A Ford-developed and patented innovation that eliminates the slight hesitation drivers feel during acceleration when the transmission upshifts into a higher gear. PowerShift sends a smooth, seamless stream of torque to the wheels for uninterrupted acceleration.

The PowerShift for the all-new Focus, for example, offers several new features including a more compliant clutch damper spring design to reduce noise levels. Aversa said the Focus shift schedule has been optimized for the wider torque band provided by the car’s 160-horsepower, direct-injected 2.0-liter engine.
I don't think the torque hole is completely eliminated, but it's very slight.
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