Thread: 7speed---6speed
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Old 12-01-2011, 01:15 PM   #13 (permalink)
wstar
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Location: Houston, TX
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Drives: too slow
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There are two separate components to the shift speed issues people bring up: control input lag and actual shift execution time. Control input lag is the one that's pretty constant, and annoying in low gears. You have to predictively click the button a bit ahead of time if the RPMs are rising very quickly in 1st or 2nd gear. In higher gears the RPMs are moving slowly enough that it's not a significant factor.

As far as actual shift execution time goes, the primary determinant is really engine RPM. The higher your RPMs are the more reliably quick the shift is. It's really a non-issue when driving the car hard, but it can feel a little slow down at pedestrian RPMs.

I've played with the UpRev 7AT torque-map (line pressure) stuff endlessly. If you set the values too high, the shifts get jerky (which isn't a good thing, it just upsets the car's balance and shocks the drivetrain). If you set them too low, the transmission doesn't achieve lockup (or doesn't achieve it as quickly), and you'll lose power and slowly lose your transmission to excess wear. The right value is determined by the power the engine is making. Setting it higher than necessary doesn't help it shift any faster.
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