US Shift 4R70W, Installation And Operation Manual

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Writing a Calibration to the Quick 2
For the changes you've made to take effect on the Quick 2 controller, you first
must write the calibration to the unit. Connect the Quick 2 to your computer
using a standard USB cord (Type A to Type B). Click the
Write Calibration
button on the toolbar to write the calibration to the controller. The Quick 2 can
now be disconnected from the computer. When the Quick 2 unit is disconnected
from the computer, the
Write Calibration button will be grayed out.
IMPORTANT INFORMATION
How to Avoid Errors
The Shiftware software gives you complete freedom and flexibility to customize
your shifting calibration however you want. This freedom requires diligence to
avoid errors.
It is
very important that the up-shift and down-shift curves for a given gear do
not cross. The up-shift point at any throttle position should usually be at least
15% greater than the down-shift point. For instance, if the 2-3 up-shift point at
½-throttle is 45MPH, then the 3-2 down-shift point should usually be less than
40MPH.
The “On-Off” differential between up-shift and down-shift points is called
Deadband (also known as Hysteresis). The more deadband you use for your
shift points, the more stable the system will be. Not using enough deadband can
result in erratic shift behavior. Too much deadband will result in sluggish
behavior due to a reluctance to down-shift.
Pay close attention to the interaction between different shifts. Overlapping the
1-2 and 2-3 shifts can cause skipped gears and other drivability problems.
Also note that torque converter slip at low speeds renders engine RPM values
meaningless. It is usually desirable to have light-throttle shift points within a low
RPM range. In this case, it is best to base light-throttle shift points on vehicle
speed rather than engine RPM (as most auto manufacturers do).